diff --git a/browser/devtools/webide/modules/runtimes.js b/browser/devtools/webide/modules/runtimes.js
index f6c3cf7ef205..d6d828cc31db 100644
--- a/browser/devtools/webide/modules/runtimes.js
+++ b/browser/devtools/webide/modules/runtimes.js
@@ -5,9 +5,9 @@
 const {Cu, Ci} = require("chrome");
 const {Devices} = Cu.import("resource://gre/modules/devtools/Devices.jsm");
 const {Services} = Cu.import("resource://gre/modules/Services.jsm");
-const {Connection} = require("devtools/client/connection-manager");
+const {Simulator} = Cu.import("resource://gre/modules/devtools/Simulator.jsm");
+const {ConnectionManager, Connection} = require("devtools/client/connection-manager");
 const {DebuggerServer} = require("resource://gre/modules/devtools/dbg-server.jsm");
-const {Simulators} = require("devtools/webide/simulators");
 const discovery = require("devtools/toolkit/discovery/discovery");
 const EventEmitter = require("devtools/toolkit/event-emitter");
 const promise = require("promise");
@@ -193,12 +193,14 @@ let SimulatorScanner = {
 
   enable() {
     this._updateRuntimes = this._updateRuntimes.bind(this);
-    Simulators.on("updated", this._updateRuntimes);
+    Simulator.on("register", this._updateRuntimes);
+    Simulator.on("unregister", this._updateRuntimes);
     this._updateRuntimes();
   },
 
   disable() {
-    Simulators.off("updated", this._updateRuntimes);
+    Simulator.off("register", this._updateRuntimes);
+    Simulator.off("unregister", this._updateRuntimes);
   },
 
   _emitUpdated() {
@@ -206,13 +208,11 @@ let SimulatorScanner = {
   },
 
   _updateRuntimes() {
-    Simulators.getAll().then(simulators => {
-      this._runtimes = [];
-      for (let simulator of simulators) {
-        this._runtimes.push(new SimulatorRuntime(simulator));
-      }
-      this._emitUpdated();
-    });
+    this._runtimes = [];
+    for (let name of Simulator.availableNames()) {
+      this._runtimes.push(new SimulatorRuntime(name));
+    }
+    this._emitUpdated();
   },
 
   scan() {
@@ -542,26 +542,28 @@ WiFiRuntime.prototype = {
 // For testing use only
 exports._WiFiRuntime = WiFiRuntime;
 
-function SimulatorRuntime(simulator) {
-  this.simulator = simulator;
+function SimulatorRuntime(name) {
+  this.name = name;
 }
 
 SimulatorRuntime.prototype = {
   type: RuntimeTypes.SIMULATOR,
   connect: function(connection) {
-    return this.simulator.launch().then(port => {
+    let port = ConnectionManager.getFreeTCPPort();
+    let simulator = Simulator.getByName(this.name);
+    if (!simulator || !simulator.launch) {
+      return promise.reject(new Error("Can't find simulator: " + this.name));
+    }
+    return simulator.launch({port: port}).then(() => {
       connection.host = "localhost";
       connection.port = port;
       connection.keepConnecting = true;
-      connection.once(Connection.Events.DISCONNECTED, e => this.simulator.kill());
+      connection.once(Connection.Events.DISCONNECTED, simulator.close);
       connection.connect();
     });
   },
   get id() {
-    return this.simulator.id;
-  },
-  get name() {
-    return this.simulator.name;
+    return this.name;
   },
 };
 
diff --git a/browser/devtools/webide/modules/simulator-process.js b/browser/devtools/webide/modules/simulator-process.js
deleted file mode 100644
index 0ebae120b0e7..000000000000
--- a/browser/devtools/webide/modules/simulator-process.js
+++ /dev/null
@@ -1,273 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/.
- */
-
-'use strict';
-
-const { Cc, Ci, Cu } = require("chrome");
-
-const Environment = require("sdk/system/environment").env;
-const Subprocess = require("sdk/system/child_process/subprocess");
-const { EventEmitter } = Cu.import("resource://gre/modules/devtools/event-emitter.js", {});
-const { Promise: promise } = Cu.import("resource://gre/modules/Promise.jsm", {});
-const { Services } = Cu.import("resource://gre/modules/Services.jsm", {});
-
-let platform = Services.appShell.hiddenDOMWindow.navigator.platform;
-let OS = "";
-if (platform.indexOf("Win") != -1) {
-  OS = "win32";
-} else if (platform.indexOf("Mac") != -1) {
-  OS = "mac64";
-} else if (platform.indexOf("Linux") != -1) {
-  if (platform.indexOf("x86_64") != -1) {
-    OS = "linux64";
-  } else {
-    OS = "linux32";
-  }
-}
-
-function SimulatorProcess() {}
-SimulatorProcess.prototype = {
-
-  // Check if B2G is running.
-  get isRunning() !!this.process,
-
-  // Start the process and connect the debugger client.
-  run() {
-
-    // Resolve B2G binary.
-    let b2g = this.b2gBinary;
-    if (!b2g || !b2g.exists()) {
-      throw Error("B2G executable not found.");
-    }
-
-    this.once("stdout", function () {
-      if (OS == "mac64") {
-        console.debug("WORKAROUND run osascript to show b2g-desktop window on OS=='mac64'");
-        // Escape double quotes and escape characters for use in AppleScript.
-        let path = b2g.path.replace(/\\/g, "\\\\").replace(/\"/g, '\\"');
-
-        Subprocess.call({
-          command: "/usr/bin/osascript",
-          arguments: ["-e", 'tell application "' + path + '" to activate'],
-        });
-      }
-    });
-
-    this.on("stdout", (e, data) => this.log(e, data.trim()));
-    this.on("stderr", (e, data) => this.log(e, data.trim()));
-
-    let environment;
-    if (OS.indexOf("linux") > -1) {
-      environment = ["TMPDIR=" + Services.dirsvc.get("TmpD", Ci.nsIFile).path];
-      if ("DISPLAY" in Environment) {
-        environment.push("DISPLAY=" + Environment.DISPLAY);
-      }
-    }
-
-    // Spawn a B2G instance.
-    this.process = Subprocess.call({
-      command: b2g,
-      arguments: this.args,
-      environment: environment,
-      stdout: data => this.emit("stdout", data),
-      stderr: data => this.emit("stderr", data),
-      // On B2G instance exit, reset tracked process, remote debugger port and
-      // shuttingDown flag, then finally emit an exit event.
-      done: result => {
-        console.log("B2G terminated with " + result.exitCode);
-        this.process = null;
-        this.emit("exit", result.exitCode);
-      }
-    });
-  },
-
-  // Request a B2G instance kill.
-  kill() {
-    let deferred = promise.defer();
-    if (this.process) {
-      this.once("exit", (e, exitCode) => {
-        this.shuttingDown = false;
-        deferred.resolve(exitCode);
-      });
-      if (!this.shuttingDown) {
-        this.shuttingDown = true;
-        this.emit("kill", null);
-        this.process.kill();
-      }
-      return deferred.promise;
-    } else {
-      return promise.resolve(undefined);
-    }
-  },
-
-  // Maybe log output messages.
-  log(level, message) {
-    if (!Services.prefs.getBoolPref("devtools.webide.logSimulatorOutput")) {
-      return;
-    }
-    if (level === "stderr" || level === "error") {
-      console.error(message);
-      return;
-    }
-    console.log(message);
-  },
-
-  // Compute B2G CLI arguments.
-  get args() {
-    let args = [];
-
-    let gaia = this.gaiaProfile;
-    if (!gaia || !gaia.exists()) {
-      throw Error("Gaia profile directory not found.");
-    }
-    args.push("-profile", gaia.path);
-
-    args.push("-start-debugger-server", "" + this.options.port);
-
-    // Ignore eventual zombie instances of b2g that are left over.
-    args.push("-no-remote");
-
-    return args;
-  },
-};
-
-EventEmitter.decorate(SimulatorProcess.prototype);
-
-
-function CustomSimulatorProcess(options) {
-  this.options = options;
-}
-
-let CSPp = CustomSimulatorProcess.prototype = Object.create(SimulatorProcess.prototype);
-
-// Compute B2G binary file handle.
-Object.defineProperty(CSPp, "b2gBinary", {
-  get: function() {
-    let file = Cc['@mozilla.org/file/local;1'].createInstance(Ci.nsILocalFile);
-    file.initWithPath(this.options.b2gBinary);
-    return file;
-  }
-});
-
-// Compute Gaia profile file handle.
-Object.defineProperty(CSPp, "gaiaProfile", {
-  get: function() {
-    let file = Cc['@mozilla.org/file/local;1'].createInstance(Ci.nsILocalFile);
-    file.initWithPath(this.options.gaiaProfile);
-    return file;
-  }
-});
-
-exports.CustomSimulatorProcess = CustomSimulatorProcess;
-
-
-function AddonSimulatorProcess(addon, options) {
-  this.addon = addon;
-  this.options = options;
-}
-
-let ASPp = AddonSimulatorProcess.prototype = Object.create(SimulatorProcess.prototype);
-
-// Compute B2G binary file handle.
-Object.defineProperty(ASPp, "b2gBinary", {
-  get: function() {
-    let file;
-    try {
-      let pref = "extensions." + this.addon.id + ".customRuntime";
-      file = Services.prefs.getComplexValue(pref, Ci.nsIFile);
-    } catch(e) {}
-
-    if (!file) {
-      let binaries = {
-        win32: "b2g-bin.exe",
-        mac64: "B2G.app/Contents/MacOS/b2g-bin",
-        linux32: "b2g-bin",
-        linux64: "b2g-bin",
-      };
-      file = this.addon.getResourceURI().QueryInterface(Ci.nsIFileURL).file;
-      file.append("b2g");
-      file.append(binaries[OS]);
-    }
-    return file;
-  }
-});
-
-// Compute Gaia profile file handle.
-Object.defineProperty(ASPp, "gaiaProfile", {
-  get: function() {
-    let file;
-    try {
-      let pref = "extensions." + this.addon.id + ".gaiaProfile";
-      file = Services.prefs.getComplexValue(pref, Ci.nsIFile);
-    } catch(e) {}
-
-    if (!file) {
-      file = this.addon.getResourceURI().QueryInterface(Ci.nsIFileURL).file;
-      file.append("profile");
-    }
-    return file;
-  }
-});
-
-exports.AddonSimulatorProcess = AddonSimulatorProcess;
-
-
-function OldAddonSimulatorProcess(addon, options) {
-  this.addon = addon;
-  this.options = options;
-}
-
-let OASPp = OldAddonSimulatorProcess.prototype = Object.create(AddonSimulatorProcess.prototype);
-
-// Compute B2G binary file handle.
-Object.defineProperty(OASPp, "b2gBinary", {
-  get: function() {
-    let file;
-    try {
-      let pref = "extensions." + this.addon.id + ".customRuntime";
-      file = Services.prefs.getComplexValue(pref, Ci.nsIFile);
-    } catch(e) {}
-
-    if (!file) {
-      let version = this.addon.name.match(/\d+\.\d+/)[0].replace(/\./, "_");
-      file = this.addon.getResourceURI().QueryInterface(Ci.nsIFileURL).file;
-      file.append("resources");
-      file.append("fxos_" + version + "_simulator");
-      file.append("data");
-      file.append(OS == "linux32" ? "linux" : OS);
-      if (OS == "mac64") {
-        file.append("B2G.app");
-        file.append("Contents");
-        file.append("MacOS");
-      } else {
-        file.append("b2g");
-      }
-      file.append("b2g-bin" + (OS == "win32" ? ".exe" : ""));
-    }
-    return file;
-  }
-});
-
-// Compute B2G CLI arguments.
-Object.defineProperty(OASPp, "args", {
-  get: function() {
-    let args = [];
-
-    let gaia = this.gaiaProfile;
-    if (!gaia || !gaia.exists()) {
-      throw Error("Gaia profile directory not found.");
-    }
-    args.push("-profile", gaia.path);
-
-    args.push("-dbgport", "" + this.options.port);
-
-    // Ignore eventual zombie instances of b2g that are left over.
-    args.push("-no-remote");
-
-    return args;
-  }
-});
-
-exports.OldAddonSimulatorProcess = OldAddonSimulatorProcess;
diff --git a/browser/devtools/webide/modules/simulators.js b/browser/devtools/webide/modules/simulators.js
deleted file mode 100644
index 2e05e91e6154..000000000000
--- a/browser/devtools/webide/modules/simulators.js
+++ /dev/null
@@ -1,96 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-const { Cu } = require("chrome");
-const { AddonManager } = Cu.import("resource://gre/modules/AddonManager.jsm");
-const { EventEmitter } = Cu.import("resource://gre/modules/devtools/event-emitter.js");
-const { ConnectionManager } = require("devtools/client/connection-manager");
-const { AddonSimulatorProcess, OldAddonSimulatorProcess } = require("devtools/webide/simulator-process");
-const promise = require("promise");
-
-const SimulatorRegExp = new RegExp(Services.prefs.getCharPref("devtools.webide.simulatorAddonRegExp"));
-
-let Simulators = {
-  // TODO (Bug 1090949) Don't generate this list from installed simulator
-  // addons, but instead implement a persistent list of user-configured
-  // simulators.
-  getAll() {
-    let deferred = promise.defer();
-    AddonManager.getAllAddons(addons => {
-      let simulators = [];
-      for (let addon of addons) {
-        if (SimulatorRegExp.exec(addon.id)) {
-          simulators.push(new Simulator(addon));
-        }
-      }
-      // Sort simulators alphabetically by name.
-      simulators.sort((a, b) => {
-        return a.name.toLowerCase().localeCompare(b.name.toLowerCase())
-      });
-      deferred.resolve(simulators);
-    });
-    return deferred.promise;
-  },
-}
-EventEmitter.decorate(Simulators);
-exports.Simulators = Simulators;
-
-function update() {
-  Simulators.emit("updated");
-}
-AddonManager.addAddonListener({
-  onEnabled: update,
-  onDisabled: update,
-  onInstalled: update,
-  onUninstalled: update
-});
-
-
-function Simulator(addon) {
-  this.addon = addon;
-}
-
-Simulator.prototype = {
-  launch() {
-    // Close already opened simulation.
-    if (this.process) {
-      return this.kill().then(this.launch.bind(this));
-    }
-
-    let options = {
-      port: ConnectionManager.getFreeTCPPort()
-    };
-
-    if (this.version <= "1.3") {
-      // Support older simulator addons.
-      this.process = new OldAddonSimulatorProcess(this.addon, options);
-    } else {
-      this.process = new AddonSimulatorProcess(this.addon, options);
-    }
-    this.process.run();
-
-    return promise.resolve(options.port);
-  },
-
-  kill() {
-    let process = this.process;
-    if (!process) {
-      return promise.resolve();
-    }
-    this.process = null;
-    return process.kill();
-  },
-
-  get id() {
-    return this.addon.id;
-  },
-
-  get name() {
-    return this.addon.name.replace(" Simulator", "");
-  },
-
-  get version() {
-    return this.name.match(/\d+\.\d+/)[0];
-  },
-};
diff --git a/browser/devtools/webide/moz.build b/browser/devtools/webide/moz.build
index 20a072793a96..e9804d09ca60 100644
--- a/browser/devtools/webide/moz.build
+++ b/browser/devtools/webide/moz.build
@@ -20,8 +20,6 @@ EXTRA_JS_MODULES.devtools.webide += [
     'modules/config-view.js',
     'modules/remote-resources.js',
     'modules/runtimes.js',
-    'modules/simulator-process.js',
-    'modules/simulators.js',
     'modules/tab-store.js',
     'modules/utils.js'
 ]
diff --git a/browser/devtools/webide/webide-prefs.js b/browser/devtools/webide/webide-prefs.js
index 6e21bec8b141..73a674449e90 100644
--- a/browser/devtools/webide/webide-prefs.js
+++ b/browser/devtools/webide/webide-prefs.js
@@ -13,7 +13,6 @@ pref("devtools.webide.enableLocalRuntime", false);
 pref("devtools.webide.addonsURL", "https://ftp.mozilla.org/pub/mozilla.org/labs/fxos-simulator/index.json");
 pref("devtools.webide.simulatorAddonsURL", "https://ftp.mozilla.org/pub/mozilla.org/labs/fxos-simulator/#VERSION#/#OS#/fxos_#SLASHED_VERSION#_simulator-#OS#-latest.xpi");
 pref("devtools.webide.simulatorAddonID", "fxos_#SLASHED_VERSION#_simulator@mozilla.org");
-pref("devtools.webide.simulatorAddonRegExp", "fxos_(.*)_simulator@mozilla\.org$");
 pref("devtools.webide.adbAddonURL", "https://ftp.mozilla.org/pub/mozilla.org/labs/fxos-simulator/adb-helper/#OS#/adbhelper-#OS#-latest.xpi");
 pref("devtools.webide.adbAddonID", "adbhelper@mozilla.org");
 pref("devtools.webide.adaptersAddonURL", "https://ftp.mozilla.org/pub/mozilla.org/labs/fxdt-adapters/#OS#/fxdt-adapters-#OS#-latest.xpi");
@@ -21,7 +20,6 @@ pref("devtools.webide.adaptersAddonID", "fxdevtools-adapters@mozilla.org");
 pref("devtools.webide.monitorWebSocketURL", "ws://localhost:9000");
 pref("devtools.webide.lastConnectedRuntime", "");
 pref("devtools.webide.lastSelectedProject", "");
-pref("devtools.webide.logSimulatorOutput", false);
 pref("devtools.webide.widget.autoinstall", true);
 #ifdef MOZ_DEV_EDITION
 pref("devtools.webide.widget.enabled", true);