diff --git a/desktop/app/src/Client.tsx b/desktop/app/src/Client.tsx
index 626af5dff..c3ca09b99 100644
--- a/desktop/app/src/Client.tsx
+++ b/desktop/app/src/Client.tsx
@@ -33,6 +33,8 @@ import {
   timeout,
   ClientQuery,
   _SandyPluginDefinition,
+  ClientResponseType,
+  ClientErrorType,
 } from 'flipper-plugin';
 import {freeze} from 'immer';
 import {message} from 'antd';
@@ -40,11 +42,6 @@ import {
   isFlipperMessageDebuggingEnabled,
   registerFlipperDebugMessage,
 } from './chrome/FlipperMessages';
-import {
-  ConnectionStatus,
-  ErrorType,
-  ClientConnection,
-} from './server/comms/ClientConnection';
 
 type Plugins = Set<string>;
 type PluginsArr = Array<string>;
@@ -65,7 +62,11 @@ export type RequestMetadata = {
   params: Params | undefined;
 };
 
-const handleError = (store: Store, device: BaseDevice, error: ErrorType) => {
+const handleError = (
+  store: Store,
+  device: BaseDevice,
+  error: ClientErrorType,
+) => {
   if (store.getState().settingsState.suppressPluginErrors) {
     return;
   }
@@ -91,13 +92,18 @@ const handleError = (store: Store, device: BaseDevice, error: ErrorType) => {
   crashReporterPlugin.instanceApi.reportCrash(payload);
 };
 
+interface ClientConnection {
+  send(data: any): void;
+  sendExpectResponse(data: any): Promise<ClientResponseType>;
+}
+
 export default class Client extends EventEmitter {
   connected = createState(false);
   id: string;
   query: ClientQuery;
   sdkVersion: number;
   messageIdCounter: number;
-  plugins: Plugins;
+  plugins: Plugins; // TODO: turn into atom, and remove eventEmitter
   backgroundPlugins: Plugins;
   connection: ClientConnection | null | undefined;
   store: Store;
@@ -138,18 +144,6 @@ export default class Client extends EventEmitter {
     this.broadcastCallbacks = new Map();
     this.activePlugins = new Set();
     this.device = device;
-
-    const client = this;
-    if (conn) {
-      conn.subscribeToEvents((status) => {
-        if (
-          status === ConnectionStatus.CLOSED ||
-          status === ConnectionStatus.ERROR
-        ) {
-          client.connected.set(false);
-        }
-      });
-    }
   }
 
   supportsPlugin(pluginId: string): boolean {
@@ -185,6 +179,7 @@ export default class Client extends EventEmitter {
         this.initPlugin(plugin);
       }
     });
+    this.emit('plugins-change');
   }
 
   initFromImport(initialStates: Record<string, Record<string, any>>): this {
@@ -194,6 +189,7 @@ export default class Client extends EventEmitter {
         this.loadPlugin(plugin, initialStates[pluginId]);
       }
     });
+    this.emit('plugins-change');
     return this;
   }
 
@@ -266,7 +262,6 @@ export default class Client extends EventEmitter {
     });
     this.emit('close');
     this.connected.set(false);
-    this.connection = undefined;
   }
 
   // clean up this client
@@ -346,7 +341,7 @@ export default class Client extends EventEmitter {
         method?: string;
         params?: Params;
         success?: Object;
-        error?: ErrorType;
+        error?: ClientErrorType;
       } = rawData;
 
       const {id, method} = data;
@@ -438,10 +433,10 @@ export default class Client extends EventEmitter {
   onResponse(
     data: {
       success?: Object;
-      error?: ErrorType;
+      error?: ClientErrorType;
     },
     resolve: ((a: any) => any) | undefined,
-    reject: (error: ErrorType) => any,
+    reject: (error: ClientErrorType) => any,
   ) {
     if (data.success) {
       resolve && resolve(data.success);
diff --git a/desktop/app/src/PluginContainer.tsx b/desktop/app/src/PluginContainer.tsx
index 04abcf747..29804037f 100644
--- a/desktop/app/src/PluginContainer.tsx
+++ b/desktop/app/src/PluginContainer.tsx
@@ -49,6 +49,7 @@ import {produce} from 'immer';
 import {reportUsage} from './utils/metrics';
 import {PluginInfo} from './chrome/fb-stubs/PluginInfo';
 import {getActiveClient, getActivePlugin} from './selectors/connections';
+import {isTest} from './utils/isProduction';
 
 const {Text, Link} = Typography;
 
@@ -250,7 +251,7 @@ class PluginContainer extends PureComponent<Props, State> {
   render() {
     const {activePlugin, pluginKey, target, pendingMessages} = this.props;
     if (!activePlugin || !target || !pluginKey) {
-      return null;
+      return this.renderNoPluginActive();
     }
     if (activePlugin.status !== 'enabled') {
       return this.renderPluginInfo();
@@ -294,6 +295,9 @@ class PluginContainer extends PureComponent<Props, State> {
   }
 
   renderNoPluginActive() {
+    if (isTest()) {
+      return <>No plugin selected</>; // to keep 'nothing' clearly recognisable in unit tests
+    }
     return (
       <View grow>
         <Waiting>
diff --git a/desktop/app/src/__tests__/PluginContainer.node.tsx b/desktop/app/src/__tests__/PluginContainer.node.tsx
index 245a3ba65..1b21db2ee 100644
--- a/desktop/app/src/__tests__/PluginContainer.node.tsx
+++ b/desktop/app/src/__tests__/PluginContainer.node.tsx
@@ -260,7 +260,9 @@ test('PluginContainer can render Sandy plugins', async () => {
 
   expect(renderer.baseElement).toMatchInlineSnapshot(`
     <body>
-      <div />
+      <div>
+        No plugin selected
+      </div>
     </body>
   `);
   expect(pluginInstance.connectedStub).toBeCalledTimes(1);
@@ -801,7 +803,9 @@ test('PluginContainer can render Sandy device plugins', async () => {
 
   expect(renderer.baseElement).toMatchInlineSnapshot(`
     <body>
-      <div />
+      <div>
+        No plugin selected
+      </div>
     </body>
   `);
   expect(pluginInstance.activatedStub).toBeCalledTimes(1);
@@ -1232,7 +1236,9 @@ test('PluginContainer can render Sandy plugins for archived devices', async () =
 
   expect(renderer.baseElement).toMatchInlineSnapshot(`
     <body>
-      <div />
+      <div>
+        No plugin selected
+      </div>
     </body>
   `);
   expect(pluginInstance.connectedStub).toBeCalledTimes(0);
diff --git a/desktop/app/src/__tests__/disconnect.node.tsx b/desktop/app/src/__tests__/disconnect.node.tsx
index 1b7100b16..1e816e137 100644
--- a/desktop/app/src/__tests__/disconnect.node.tsx
+++ b/desktop/app/src/__tests__/disconnect.node.tsx
@@ -213,7 +213,7 @@ test('new clients replace old ones', async () => {
       },
     },
   );
-  const {client, store, device, createClient} =
+  const {client, store, device, createClient, logger} =
     await createMockFlipperWithPlugin(plugin, {
       asBackgroundPlugin: true,
     });
@@ -225,7 +225,7 @@ test('new clients replace old ones', async () => {
   expect(instance.instanceApi.disconnect).toBeCalledTimes(0);
 
   const client2 = await createClient(device, 'AnotherApp', client.query, true);
-  handleClientConnected(store, client2);
+  handleClientConnected(null as any, store, logger, client2);
 
   expect(client2.connected.get()).toBe(true);
   const instance2 = client2.sandyPluginStates.get(plugin.id)!;
diff --git a/desktop/app/src/dispatcher/__tests__/handleOpenPluginDeeplink.node.tsx b/desktop/app/src/dispatcher/__tests__/handleOpenPluginDeeplink.node.tsx
index 6ac5c541b..150f7e361 100644
--- a/desktop/app/src/dispatcher/__tests__/handleOpenPluginDeeplink.node.tsx
+++ b/desktop/app/src/dispatcher/__tests__/handleOpenPluginDeeplink.node.tsx
@@ -193,9 +193,11 @@ test('triggering a deeplink without applicable device can wait for a device', as
   );
   expect(renderer.baseElement).toMatchInlineSnapshot(`
     <body>
-      <div />
+      <div>
+        No plugin selected
+      </div>
     </body>
-    `);
+  `);
 
   const handlePromise = handleDeeplink(
     store,
@@ -207,9 +209,11 @@ test('triggering a deeplink without applicable device can wait for a device', as
 
   // No device yet available (dialogs are not renderable atm)
   expect(renderer.baseElement).toMatchInlineSnapshot(`
-      <body>
-        <div />
-      </body>
+    <body>
+      <div>
+        No plugin selected
+      </div>
+    </body>
   `);
 
   // create a new device
@@ -273,9 +277,11 @@ test('triggering a deeplink without applicable client can wait for a device', as
   );
   expect(renderer.baseElement).toMatchInlineSnapshot(`
     <body>
-      <div />
+      <div>
+        No plugin selected
+      </div>
     </body>
-    `);
+  `);
 
   const handlePromise = handleDeeplink(
     store,
@@ -288,7 +294,9 @@ test('triggering a deeplink without applicable client can wait for a device', as
   // No device yet available (dialogs are not renderable atm)
   expect(renderer.baseElement).toMatchInlineSnapshot(`
     <body>
-      <div />
+      <div>
+        No plugin selected
+      </div>
     </body>
   `);
 
diff --git a/desktop/app/src/dispatcher/flipperServer.tsx b/desktop/app/src/dispatcher/flipperServer.tsx
index 3ce945408..406c63f67 100644
--- a/desktop/app/src/dispatcher/flipperServer.tsx
+++ b/desktop/app/src/dispatcher/flipperServer.tsx
@@ -8,13 +8,16 @@
  */
 
 import React from 'react';
-import {Store} from '../reducers/index';
+import {State, Store} from '../reducers/index';
 import {Logger} from '../fb-interfaces/Logger';
 import {FlipperServerImpl} from '../server/FlipperServerImpl';
 import {selectClient, selectDevice} from '../reducers/connections';
 import Client from '../Client';
 import {notification} from 'antd';
 import BaseDevice from '../devices/BaseDevice';
+import {ClientDescription, timeout} from 'flipper-plugin';
+import {reportPlatformFailures} from '../utils/metrics';
+import {sideEffect} from '../utils/sideEffect';
 
 export default async (store: Store, logger: Logger) => {
   const {enableAndroid, androidHome, idbPath, enableIOS, enablePhysicalIOS} =
@@ -111,11 +114,20 @@ export default async (store: Store, logger: Logger) => {
     // N.B.: note that we don't remove the device, we keep it in offline
   });
 
-  server.on('client-connected', (payload) =>
-    // TODO: fixed later in this stack
-    handleClientConnected(store, payload as any),
+  server.on('client-connected', (payload: ClientDescription) =>
+    handleClientConnected(server, store, logger, payload),
   );
 
+  server.on('client-disconnected', ({id}) => {
+    const existingClient = store.getState().connections.clients.get(id);
+    existingClient?.disconnect();
+  });
+
+  server.on('client-message', ({id, message}) => {
+    const existingClient = store.getState().connections.clients.get(id);
+    existingClient?.onMessage(message);
+  });
+
   if (typeof window !== 'undefined') {
     window.addEventListener('beforeunload', () => {
       server.close();
@@ -142,25 +154,51 @@ export default async (store: Store, logger: Logger) => {
   };
 };
 
-export async function handleClientConnected(store: Store, client: Client) {
+export async function handleClientConnected(
+  server: FlipperServerImpl,
+  store: Store,
+  logger: Logger,
+  {id, query}: ClientDescription,
+) {
   const {connections} = store.getState();
-  const existingClient = connections.clients.get(client.id);
+  const existingClient = connections.clients.get(id);
 
   if (existingClient) {
     existingClient.destroy();
     store.dispatch({
       type: 'CLEAR_CLIENT_PLUGINS_STATE',
       payload: {
-        clientId: client.id,
+        clientId: id,
         devicePlugins: new Set(),
       },
     });
     store.dispatch({
       type: 'CLIENT_REMOVED',
-      payload: client.id,
+      payload: id,
     });
   }
 
+  const device =
+    getDeviceBySerial(store.getState(), query.device_id) ??
+    (await findDeviceForConnection(store, query.app, query.device_id));
+
+  const client = new Client(
+    id,
+    query,
+    {
+      send(data: any) {
+        server.exec('client-request', id, data);
+      },
+      async sendExpectResponse(data: any) {
+        return await server.exec('client-request-response', id, data);
+      },
+    },
+    logger,
+    store,
+    undefined,
+    device,
+  );
+
   console.debug(
     `Device client initialized: ${client.id}. Supported plugins: ${Array.from(
       client.plugins,
@@ -174,5 +212,64 @@ export async function handleClientConnected(store: Store, client: Client) {
   });
 
   store.dispatch(selectClient(client.id));
-  client.emit('plugins-change');
+
+  await timeout(
+    30 * 1000,
+    client.init(),
+    `[conn] Failed to initialize client ${query.app} on ${query.device_id} in a timely manner`,
+  );
+}
+
+function getDeviceBySerial(
+  state: State,
+  serial: string,
+): BaseDevice | undefined {
+  return state.connections.devices.find((device) => device.serial === serial);
+}
+
+async function findDeviceForConnection(
+  store: Store,
+  clientId: string,
+  serial: string,
+): Promise<BaseDevice> {
+  let lastSeenDeviceList: BaseDevice[] = [];
+  /* All clients should have a corresponding Device in the store.
+     However, clients can connect before a device is registered, so wait a
+     while for the device to be registered if it isn't already. */
+  return reportPlatformFailures(
+    new Promise<BaseDevice>((resolve, reject) => {
+      let unsubscribe: () => void = () => {};
+
+      const timeout = setTimeout(() => {
+        unsubscribe();
+        const error = `Timed out waiting for device ${serial} for client ${clientId}`;
+        console.error(
+          '[conn] Unable to find device for connection. Error:',
+          error,
+        );
+        reject(error);
+      }, 15000);
+      unsubscribe = sideEffect(
+        store,
+        {name: 'waitForDevice', throttleMs: 100},
+        (state) => state.connections.devices,
+        (newDeviceList) => {
+          if (newDeviceList === lastSeenDeviceList) {
+            return;
+          }
+          lastSeenDeviceList = newDeviceList;
+          const matchingDevice = newDeviceList.find(
+            (device) => device.serial === serial,
+          );
+          if (matchingDevice) {
+            console.log(`[conn] Found device for: ${clientId} on ${serial}.`);
+            clearTimeout(timeout);
+            resolve(matchingDevice);
+            unsubscribe();
+          }
+        },
+      );
+    }),
+    'client-setMatchingDevice',
+  );
 }
diff --git a/desktop/app/src/dispatcher/pluginsChangeListener.tsx b/desktop/app/src/dispatcher/pluginsChangeListener.tsx
index f15a6c09f..0594dc1da 100644
--- a/desktop/app/src/dispatcher/pluginsChangeListener.tsx
+++ b/desktop/app/src/dispatcher/pluginsChangeListener.tsx
@@ -23,7 +23,7 @@ export default (store: Store, _logger: Logger) => {
 
   sideEffect(
     store,
-    {name: 'pluginsChangeListener', throttleMs: 100, fireImmediately: true},
+    {name: 'pluginsChangeListener', throttleMs: 10, fireImmediately: true},
     getActiveClient,
     (activeClient, _store) => {
       if (activeClient !== prevClient) {
@@ -33,6 +33,7 @@ export default (store: Store, _logger: Logger) => {
         prevClient = activeClient;
         if (prevClient) {
           prevClient.on('plugins-change', onActiveAppPluginListChanged);
+          store.dispatch(appPluginListChanged()); // force refresh
         }
       }
     },
diff --git a/desktop/app/src/server/FlipperServerImpl.tsx b/desktop/app/src/server/FlipperServerImpl.tsx
index 0284cdd1f..c340ff6f3 100644
--- a/desktop/app/src/server/FlipperServerImpl.tsx
+++ b/desktop/app/src/server/FlipperServerImpl.tsx
@@ -8,7 +8,6 @@
  */
 
 import EventEmitter from 'events';
-import Client from '../Client';
 import {Store} from '../reducers/index';
 import {Logger} from '../fb-interfaces/Logger';
 import ServerController from './comms/ServerController';
@@ -91,10 +90,6 @@ export class FlipperServerImpl implements FlipperServer {
     this.android = new AndroidDeviceManager(this);
     this.ios = new IOSDeviceManager(this);
 
-    server.addListener('new-client', (client: Client) => {
-      this.emit('client-connected', client);
-    });
-
     server.addListener('error', (err) => {
       this.emit('server-error', err);
     });
@@ -263,6 +258,25 @@ export class FlipperServerImpl implements FlipperServer {
       }
       device.sendCommand(command);
     },
+    'client-request': async (clientId, payload) => {
+      this.server.connections.get(clientId)?.connection?.send(payload);
+    },
+    'client-request-response': async (clientId, payload) => {
+      const client = this.server.connections.get(clientId);
+      if (client && client.connection) {
+        return await client.connection.sendExpectResponse(payload);
+      }
+      return {
+        length: 0,
+        error: {
+          message: `Client '${clientId} is no longer connected, failed to deliver: ${JSON.stringify(
+            payload,
+          )}`,
+          name: 'CLIENT_DISCONNECTED',
+          stacktrace: '',
+        },
+      };
+    },
   };
 
   registerDevice(device: ServerDevice) {
diff --git a/desktop/app/src/server/comms/BrowserClientFlipperConnection.tsx b/desktop/app/src/server/comms/BrowserClientFlipperConnection.tsx
index 4e907e162..bd91cb6fd 100644
--- a/desktop/app/src/server/comms/BrowserClientFlipperConnection.tsx
+++ b/desktop/app/src/server/comms/BrowserClientFlipperConnection.tsx
@@ -7,12 +7,12 @@
  * @format
  */
 
+import {ClientResponseType} from 'flipper-plugin';
 import WebSocket from 'ws';
 import {
   ConnectionStatusChange,
   ConnectionStatus,
   ClientConnection,
-  ResponseType,
 } from './ClientConnection';
 
 export class BrowserClientFlipperConnection implements ClientConnection {
@@ -40,7 +40,7 @@ export class BrowserClientFlipperConnection implements ClientConnection {
       }),
     );
   }
-  sendExpectResponse(data: any): Promise<ResponseType> {
+  sendExpectResponse(data: any): Promise<ClientResponseType> {
     return new Promise((resolve, reject) => {
       const {id: callId = undefined, method = undefined} =
         data != null ? data : {};
diff --git a/desktop/app/src/server/comms/ClientConnection.tsx b/desktop/app/src/server/comms/ClientConnection.tsx
index 0192a8249..46bb5b58e 100644
--- a/desktop/app/src/server/comms/ClientConnection.tsx
+++ b/desktop/app/src/server/comms/ClientConnection.tsx
@@ -7,17 +7,7 @@
  * @format
  */
 
-export type ErrorType = {
-  message: string;
-  stacktrace: string;
-  name: string;
-};
-
-export type ResponseType = {
-  success?: Object;
-  error?: ErrorType;
-  length: number;
-};
+import {ClientResponseType} from 'flipper-plugin';
 
 export enum ConnectionStatus {
   ERROR = 'error',
@@ -33,5 +23,5 @@ export interface ClientConnection {
   subscribeToEvents(subscriber: ConnectionStatusChange): void;
   close(): void;
   send(data: any): void;
-  sendExpectResponse(data: any): Promise<ResponseType>;
+  sendExpectResponse(data: any): Promise<ClientResponseType>;
 }
diff --git a/desktop/app/src/server/comms/ServerAdapter.tsx b/desktop/app/src/server/comms/ServerAdapter.tsx
index 2a42425e1..3521e6cb6 100644
--- a/desktop/app/src/server/comms/ServerAdapter.tsx
+++ b/desktop/app/src/server/comms/ServerAdapter.tsx
@@ -11,10 +11,9 @@ import {
   CertificateExchangeMedium,
   SecureServerConfig,
 } from '../utils/CertificateProvider';
-import Client from '../../Client';
 import {ClientConnection} from './ClientConnection';
 import {transformCertificateExchangeMediumToType} from './Utilities';
-import {ClientQuery} from 'flipper-plugin';
+import {ClientDescription, ClientQuery} from 'flipper-plugin';
 
 /**
  * ClientCsrQuery defines a client query with CSR
@@ -87,7 +86,7 @@ export interface ServerEventsListener {
   onConnectionCreated(
     clientQuery: SecureClientQuery,
     clientConnection: ClientConnection,
-  ): Promise<Client>;
+  ): Promise<ClientDescription>;
   /**
    * A connection with a client has been closed.
    * @param id The client identifier.
@@ -98,6 +97,11 @@ export interface ServerEventsListener {
    * @param error An Error instance.
    */
   onError(error: Error): void;
+  /**
+   * A message was received for a specif client
+   * // TODO: payload should become JSON
+   */
+  onClientMessage(clientId: string, payload: string): void;
 }
 
 /**
diff --git a/desktop/app/src/server/comms/ServerController.tsx b/desktop/app/src/server/comms/ServerController.tsx
index b4f14e471..240dfb73a 100644
--- a/desktop/app/src/server/comms/ServerController.tsx
+++ b/desktop/app/src/server/comms/ServerController.tsx
@@ -9,10 +9,9 @@
 
 import {CertificateExchangeMedium} from '../utils/CertificateProvider';
 import {Logger} from '../../fb-interfaces/Logger';
-import {ClientQuery} from 'flipper-plugin';
-import {Store, State} from '../../reducers/index';
+import {ClientDescription, ClientQuery} from 'flipper-plugin';
+import {Store} from '../../reducers/index';
 import CertificateProvider from '../utils/CertificateProvider';
-import Client from '../../Client';
 import {ClientConnection, ConnectionStatus} from './ClientConnection';
 import {UninitializedClient} from '../UninitializedClient';
 import {reportPlatformFailures} from '../../utils/metrics';
@@ -21,8 +20,6 @@ import invariant from 'invariant';
 import GK from '../../fb-stubs/GK';
 import {buildClientId} from '../../utils/clientUtils';
 import DummyDevice from '../../server/devices/DummyDevice';
-import BaseDevice from '../../devices/BaseDevice';
-import {sideEffect} from '../../utils/sideEffect';
 import {
   appNameWithUpdateHint,
   transformCertificateExchangeMediumToType,
@@ -38,11 +35,10 @@ import {
 } from './ServerFactory';
 import {FlipperServerImpl} from '../FlipperServerImpl';
 import {isTest} from '../../utils/isProduction';
-import {timeout} from 'flipper-plugin';
 
 type ClientInfo = {
   connection: ClientConnection | null | undefined;
-  client: Client;
+  client: ClientDescription;
 };
 
 type ClientCsrQuery = {
@@ -51,9 +47,7 @@ type ClientCsrQuery = {
 };
 
 declare interface ServerController {
-  on(event: 'new-client', callback: (client: Client) => void): this;
   on(event: 'error', callback: (err: Error) => void): this;
-  on(event: 'clients-change', callback: () => void): this;
 }
 
 /**
@@ -99,6 +93,13 @@ class ServerController extends EventEmitter implements ServerEventsListener {
     this.initialized = null;
   }
 
+  onClientMessage(clientId: string, payload: string): void {
+    this.flipperServer.emit('client-message', {
+      id: clientId,
+      message: payload,
+    });
+  }
+
   get logger(): Logger {
     return this.flipperServer.logger;
   }
@@ -188,7 +189,7 @@ class ServerController extends EventEmitter implements ServerEventsListener {
   onConnectionCreated(
     clientQuery: SecureClientQuery,
     clientConnection: ClientConnection,
-  ): Promise<Client> {
+  ): Promise<ClientDescription> {
     const {app, os, device, device_id, sdk_version, csr, csr_path, medium} =
       clientQuery;
     const transformedMedium = transformCertificateExchangeMediumToType(medium);
@@ -334,7 +335,7 @@ class ServerController extends EventEmitter implements ServerEventsListener {
     connection: ClientConnection,
     query: ClientQuery & {medium: CertificateExchangeMedium},
     csrQuery: ClientCsrQuery,
-  ): Promise<Client> {
+  ): Promise<ClientDescription> {
     invariant(query, 'expected query');
 
     // try to get id by comparing giving `csr` to file from `csr_path`
@@ -371,20 +372,11 @@ class ServerController extends EventEmitter implements ServerEventsListener {
     console.log(
       `[conn] Matching device for ${query.app} on ${query.device_id}...`,
     );
-    // TODO: grab device from flipperServer.devices instead of store
-    const device =
-      getDeviceBySerial(this.store.getState(), query.device_id) ??
-      (await findDeviceForConnection(this.store, query.app, query.device_id));
 
-    const client = new Client(
+    const client: ClientDescription = {
       id,
       query,
-      connection,
-      this.logger,
-      this.store,
-      undefined,
-      device,
-    );
+    };
 
     const info = {
       client,
@@ -395,12 +387,6 @@ class ServerController extends EventEmitter implements ServerEventsListener {
       `[conn] Initializing client ${query.app} on ${query.device_id}...`,
     );
 
-    await timeout(
-      30 * 1000,
-      client.init(),
-      `[conn] Failed to initialize client ${query.app} on ${query.device_id} in a timely manner`,
-    );
-
     connection.subscribeToEvents((status: ConnectionStatus) => {
       if (
         status === ConnectionStatus.CLOSED ||
@@ -410,12 +396,7 @@ class ServerController extends EventEmitter implements ServerEventsListener {
       }
     });
 
-    console.debug(
-      `[conn] Device client initialized: ${id}. Supported plugins: ${Array.from(
-        client.plugins,
-      ).join(', ')}`,
-      'server',
-    );
+    console.debug(`[conn] Device client initialized: ${id}.`, 'server');
 
     /* If a device gets disconnected without being cleaned up properly,
      * Flipper won't be aware until it attempts to reconnect.
@@ -435,14 +416,12 @@ class ServerController extends EventEmitter implements ServerEventsListener {
     }
 
     this.connections.set(id, info);
-    this.emit('new-client', client);
-    this.emit('clients-change');
-    client.emit('plugins-change');
+    this.flipperServer.emit('client-connected', client);
 
     return client;
   }
 
-  attachFakeClient(client: Client) {
+  attachFakeClient(client: ClientDescription) {
     this.connections.set(client.id, {
       client,
       connection: null,
@@ -460,10 +439,8 @@ class ServerController extends EventEmitter implements ServerEventsListener {
       console.log(
         `[conn] Disconnected: ${info.client.query.app} on ${info.client.query.device_id}.`,
       );
-      info.client.disconnect();
+      this.flipperServer.emit('client-disconnected', {id});
       this.connections.delete(id);
-      this.emit('clients-change');
-      this.emit('removed-client', id);
     }
   }
 }
@@ -499,60 +476,6 @@ class ConnectionTracker {
   }
 }
 
-function getDeviceBySerial(
-  state: State,
-  serial: string,
-): BaseDevice | undefined {
-  return state.connections.devices.find((device) => device.serial === serial);
-}
-
-async function findDeviceForConnection(
-  store: Store,
-  clientId: string,
-  serial: string,
-): Promise<BaseDevice> {
-  let lastSeenDeviceList: BaseDevice[] = [];
-  /* All clients should have a corresponding Device in the store.
-     However, clients can connect before a device is registered, so wait a
-     while for the device to be registered if it isn't already. */
-  return reportPlatformFailures(
-    new Promise<BaseDevice>((resolve, reject) => {
-      let unsubscribe: () => void = () => {};
-
-      const timeout = setTimeout(() => {
-        unsubscribe();
-        const error = `Timed out waiting for device ${serial} for client ${clientId}`;
-        console.error(
-          '[conn] Unable to find device for connection. Error:',
-          error,
-        );
-        reject(error);
-      }, 15000);
-      unsubscribe = sideEffect(
-        store,
-        {name: 'waitForDevice', throttleMs: 100},
-        (state) => state.connections.devices,
-        (newDeviceList) => {
-          if (newDeviceList === lastSeenDeviceList) {
-            return;
-          }
-          lastSeenDeviceList = newDeviceList;
-          const matchingDevice = newDeviceList.find(
-            (device) => device.serial === serial,
-          );
-          if (matchingDevice) {
-            console.log(`[conn] Found device for: ${clientId} on ${serial}.`);
-            clearTimeout(timeout);
-            resolve(matchingDevice);
-            unsubscribe();
-          }
-        },
-      );
-    }),
-    'client-setMatchingDevice',
-  );
-}
-
 export default ServerController;
 
 function clientQueryToKey(clientQuery: ClientQuery): string {
diff --git a/desktop/app/src/server/comms/ServerRSocket.tsx b/desktop/app/src/server/comms/ServerRSocket.tsx
index 9123091ec..d66c59d98 100644
--- a/desktop/app/src/server/comms/ServerRSocket.tsx
+++ b/desktop/app/src/server/comms/ServerRSocket.tsx
@@ -17,15 +17,17 @@ import net, {Socket} from 'net';
 import {RSocketServer} from 'rsocket-core';
 import RSocketTCPServer from 'rsocket-tcp-server';
 import {Payload, ReactiveSocket, Responder} from 'rsocket-types';
-import Client from '../../Client';
 import {Single} from 'rsocket-flowable';
 import {
   ClientConnection,
   ConnectionStatusChange,
   ConnectionStatus,
-  ResponseType,
 } from './ClientConnection';
-import {ClientQuery} from 'flipper-plugin';
+import {
+  ClientDescription,
+  ClientQuery,
+  ClientResponseType,
+} from 'flipper-plugin';
 
 /**
  * RSocket based server. RSocket uses its own protocol for communication between
@@ -153,7 +155,7 @@ class ServerRSocket extends ServerAdapter {
             })
             .subscribe({
               onComplete: (payload: Payload<any, any>) => {
-                const response: ResponseType = JSON.parse(payload.data);
+                const response: ClientResponseType = JSON.parse(payload.data);
                 response.length = payload.data.length;
                 resolve(response);
               },
@@ -165,11 +167,9 @@ class ServerRSocket extends ServerAdapter {
       },
     };
 
-    let resolvedClient: Client | undefined;
-    const client: Promise<Client> = this.listener.onConnectionCreated(
-      clientQuery,
-      clientConnection,
-    );
+    let resolvedClient: ClientDescription | undefined;
+    const client: Promise<ClientDescription> =
+      this.listener.onConnectionCreated(clientQuery, clientConnection);
     client
       .then((client) => {
         console.log(
@@ -184,12 +184,12 @@ class ServerRSocket extends ServerAdapter {
     return {
       fireAndForget: (payload: {data: string}) => {
         if (resolvedClient) {
-          resolvedClient.onMessage(payload.data);
+          this.listener.onClientMessage(resolvedClient.id, payload.data);
         } else {
           client &&
             client
               .then((client) => {
-                client.onMessage(payload.data);
+                this.listener.onClientMessage(client.id, payload.data);
               })
               .catch((e) => {
                 console.error('Could not deliver message: ', e);
diff --git a/desktop/app/src/server/comms/ServerWebSocket.tsx b/desktop/app/src/server/comms/ServerWebSocket.tsx
index 18e0daa94..26ce8f8e9 100644
--- a/desktop/app/src/server/comms/ServerWebSocket.tsx
+++ b/desktop/app/src/server/comms/ServerWebSocket.tsx
@@ -12,15 +12,18 @@ import WebSocket from 'ws';
 import ws from 'ws';
 import {SecureClientQuery, ServerEventsListener} from './ServerAdapter';
 import querystring from 'querystring';
-import Client from '../../Client';
 import {
   ClientConnection,
   ConnectionStatus,
   ConnectionStatusChange,
-  ErrorType,
 } from './ClientConnection';
 import {IncomingMessage} from 'http';
-import {ClientQuery, DeviceOS} from 'flipper-plugin';
+import {
+  ClientDescription,
+  ClientErrorType,
+  ClientQuery,
+  DeviceOS,
+} from 'flipper-plugin';
 
 /**
  * WebSocket-based server.
@@ -121,11 +124,9 @@ class ServerWebSocket extends ServerWebSocketBase {
       },
     };
 
-    let resolvedClient: Client | undefined;
-    const client: Promise<Client> = this.listener.onConnectionCreated(
-      clientQuery,
-      clientConnection,
-    );
+    let resolvedClient: ClientDescription | undefined;
+    const client: Promise<ClientDescription> =
+      this.listener.onConnectionCreated(clientQuery, clientConnection);
     client
       .then((client) => (resolvedClient = client))
       .catch((e) => {
@@ -147,7 +148,7 @@ class ServerWebSocket extends ServerWebSocketBase {
       const data: {
         id?: number;
         success?: Object | undefined;
-        error?: ErrorType | undefined;
+        error?: ClientErrorType | undefined;
       } = json;
 
       if (data.hasOwnProperty('id') && data.id !== undefined) {
@@ -165,14 +166,19 @@ class ServerWebSocket extends ServerWebSocketBase {
         }
       } else {
         if (resolvedClient) {
-          resolvedClient.onMessage(message);
+          this.listener.onClientMessage(resolvedClient.id, message);
         } else {
           client &&
             client
               .then((client) => {
-                client.onMessage(message);
+                this.listener.onClientMessage(client.id, message);
               })
-              .catch((_) => {});
+              .catch((e) => {
+                console.warn(
+                  'Could not deliver message, client did not resolve. ',
+                  e,
+                );
+              });
         }
       }
     });
diff --git a/desktop/app/src/server/comms/ServerWebSocketBrowser.tsx b/desktop/app/src/server/comms/ServerWebSocketBrowser.tsx
index 2407c41ad..bc2627b32 100644
--- a/desktop/app/src/server/comms/ServerWebSocketBrowser.tsx
+++ b/desktop/app/src/server/comms/ServerWebSocketBrowser.tsx
@@ -10,13 +10,12 @@
 import ServerWebSocketBase from './ServerWebSocketBase';
 import WebSocket from 'ws';
 import querystring from 'querystring';
-import Client from '../../Client';
 import {BrowserClientFlipperConnection} from './BrowserClientFlipperConnection';
 import {ServerEventsListener} from './ServerAdapter';
 import constants from '../../fb-stubs/constants';
 import ws from 'ws';
 import {IncomingMessage} from 'http';
-import {ClientQuery} from 'flipper-plugin';
+import {ClientDescription, ClientQuery} from 'flipper-plugin';
 
 /**
  * WebSocket-based server which uses a connect/disconnect handshake over an insecure channel.
@@ -47,7 +46,7 @@ class ServerWebSocketBrowser extends ServerWebSocketBase {
    */
   onConnection(ws: WebSocket, message: any): void {
     const clients: {
-      [app: string]: Promise<Client>;
+      [app: string]: Promise<ClientDescription>;
     } = {};
 
     /**
@@ -113,12 +112,13 @@ class ServerWebSocketBrowser extends ServerWebSocketBase {
             `[conn] Local websocket connection established: ${clientQuery.app} on ${clientQuery.device_id}.`,
           );
 
-          let resolvedClient: Client | null = null;
+          let resolvedClient: ClientDescription | null = null;
           this.listener.onSecureConnectionAttempt(extendedClientQuery);
-          const client: Promise<Client> = this.listener.onConnectionCreated(
-            extendedClientQuery,
-            clientConnection,
-          );
+          const client: Promise<ClientDescription> =
+            this.listener.onConnectionCreated(
+              extendedClientQuery,
+              clientConnection,
+            );
           client
             .then((client) => {
               console.log(
@@ -148,9 +148,17 @@ class ServerWebSocketBrowser extends ServerWebSocketBase {
             if (parsed.app === app && parsed.payload?.id == null) {
               const message = JSON.stringify(parsed.payload);
               if (resolvedClient) {
-                resolvedClient.onMessage(message);
+                this.listener.onClientMessage(resolvedClient.id, message);
               } else {
-                client.then((c) => c.onMessage(message)).catch((_) => {});
+                client
+                  .then((c) => this.listener.onClientMessage(c.id, message))
+                  .catch((e) => {
+                    console.warn(
+                      'Could not deliver message, client did not resolve: ' +
+                        app,
+                      e,
+                    );
+                  });
               }
             }
           });
diff --git a/desktop/app/src/server/devices/android/adbClient.tsx b/desktop/app/src/server/devices/android/adbClient.tsx
index 833b2a92a..64de7c469 100644
--- a/desktop/app/src/server/devices/android/adbClient.tsx
+++ b/desktop/app/src/server/devices/android/adbClient.tsx
@@ -9,12 +9,10 @@
 
 import {reportPlatformFailures} from '../../../utils/metrics';
 import {execFile} from 'promisify-child-process';
-import promiseRetry from 'promise-retry';
 import adbConfig from './adbConfig';
 import adbkit, {Client} from 'adbkit';
 import path from 'path';
 
-const MAX_RETRIES = 5;
 let instance: Promise<Client>;
 
 type Config = {
diff --git a/desktop/flipper-plugin/src/types/server-types.tsx b/desktop/flipper-plugin/src/types/server-types.tsx
index 04e766cbe..833ca9011 100644
--- a/desktop/flipper-plugin/src/types/server-types.tsx
+++ b/desktop/flipper-plugin/src/types/server-types.tsx
@@ -51,7 +51,18 @@ export type ClientQuery = {
 export type ClientDescription = {
   readonly id: string;
   readonly query: ClientQuery;
-  readonly sdkVersion: number;
+};
+
+export type ClientErrorType = {
+  message: string;
+  stacktrace: string;
+  name: string;
+};
+
+export type ClientResponseType = {
+  success?: Object;
+  error?: ClientErrorType;
+  length: number;
 };
 
 export type FlipperServerEvents = {
@@ -64,11 +75,16 @@ export type FlipperServerEvents = {
   };
   'device-connected': DeviceDescription;
   'device-disconnected': DeviceDescription;
-  'client-connected': ClientDescription;
   'device-log': {
     serial: string;
     entry: DeviceLogEntry;
   };
+  'client-connected': ClientDescription;
+  'client-disconnected': {id: string};
+  'client-message': {
+    id: string;
+    message: string;
+  };
 };
 
 export type FlipperServerCommands = {
@@ -91,6 +107,11 @@ export type FlipperServerCommands = {
   'device-clear-logs': (serial: string) => Promise<void>;
   'device-navigate': (serial: string, location: string) => Promise<void>;
   'metro-command': (serial: string, command: string) => Promise<void>;
+  'client-request': (clientId: string, payload: any) => Promise<void>;
+  'client-request-response': (
+    clientId: string,
+    payload: any,
+  ) => Promise<ClientResponseType>;
 };
 
 export interface FlipperServer {