--- a/devtools/shim/aboutdevtools/aboutdevtools.js
+++ b/devtools/shim/aboutdevtools/aboutdevtools.js
@@ -4,16 +4,22 @@
 
 "use strict";
 
 const { utils: Cu } = Components;
 const { Services } = Cu.import("resource://gre/modules/Services.jsm", {});
 
 const DEVTOOLS_ENABLED_PREF = "devtools.enabled";
 
+const TELEMETRY_OPENED_KEY = "DEVTOOLS_ABOUT_DEVTOOLS_OPENED_KEY";
+const TELEMETRY_OPENED_REASON = "DEVTOOLS_ABOUT_DEVTOOLS_OPENED_REASON";
+const TELEMETRY_OPENED = "devtools.aboutdevtools.opened";
+const TELEMETRY_INSTALLED = "devtools.aboutdevtools.installed";
+const TELEMETRY_NOINSTALL_EXITS = "devtools.aboutdevtools.noinstall_exits";
+
 const MESSAGES = {
   AboutDebugging: "about-debugging-message",
   ContextMenu: "inspect-element-message",
   HamburgerMenu: "menu-message",
   KeyShortcut: "key-shortcut-message",
   SystemMenu: "menu-message",
 };
 
@@ -22,25 +28,35 @@ const aboutDevtoolsBundle = Services.str
 
 const KEY_SHORTCUTS_STRINGS = "chrome://devtools-shim/locale/key-shortcuts.properties";
 const keyShortcutsBundle = Services.strings.createBundle(KEY_SHORTCUTS_STRINGS);
 
 // URL constructor doesn't support about: scheme,
 // we have to use http in order to have working searchParams.
 let url = new URL(window.location.href.replace("about:", "http://"));
 let reason = url.searchParams.get("reason");
+let keyid = url.searchParams.get("keyid");
 let tabid = parseInt(url.searchParams.get("tabid"), 10);
 
+// Keep track of the initial devtools.enabled value to track exits in telemetry.
+let isEnabledOnLoad;
+
 function getToolboxShortcut() {
   const modifier = Services.appinfo.OS == "Darwin" ? "Cmd+Opt+" : "Ctrl+Shift+";
   return modifier + keyShortcutsBundle.GetStringFromName("toggleToolbox.commandkey");
 }
 
 function onInstallButtonClick() {
   Services.prefs.setBoolPref("devtools.enabled", true);
+
+  try {
+    Services.telemetry.scalarAdd(TELEMETRY_INSTALLED, 1);
+  } catch (e) {
+    dump("about:devtools oninstall telemetry failed: " + e + "\n");
+  }
 }
 
 function onCloseButtonClick() {
   window.close();
 }
 
 function updatePage() {
   const installPage = document.getElementById("install-page");
@@ -164,16 +180,30 @@ window.addEventListener("load", function
 
   let featuresContainer = document.querySelector(".features-list");
   for (let feature of features) {
     featuresContainer.appendChild(createFeatureEl(feature));
   }
 
   // Update the current page based on the current value of DEVTOOLS_ENABLED_PREF.
   updatePage();
+
+  try {
+    if (reason) {
+      Services.telemetry.getHistogramById(TELEMETRY_OPENED_REASON).add(reason);
+    }
+
+    if (keyid) {
+      Services.telemetry.getHistogramById(TELEMETRY_OPENED_KEY).add(keyid);
+    }
+
+    Services.telemetry.scalarAdd(TELEMETRY_OPENED, 1);
+  } catch (e) {
+    dump("about:devtools onload telemetry failed: " + e + "\n");
+  }
 }, { once: true });
 
 window.addEventListener("beforeunload", function () {
   // Focus the tab that triggered the DevTools onboarding.
   if (document.visibilityState != "visible") {
     // Only try to focus the correct tab if the current tab is the about:devtools page.
     return;
   }
@@ -189,9 +219,18 @@ window.addEventListener("beforeunload", 
     gBrowser.selectedTab = originalTab;
   }
 }, {once: true});
 
 window.addEventListener("unload", function () {
   document.getElementById("install").removeEventListener("click", onInstallButtonClick);
   document.getElementById("close").removeEventListener("click", onCloseButtonClick);
   Services.prefs.removeObserver(DEVTOOLS_ENABLED_PREF, updatePage);
+
+  const isEnabled = Services.prefs.getBoolPref("devtools.enabled");
+  if (!isEnabledOnLoad && !isEnabled) {
+    try {
+      Services.telemetry.scalarAdd(TELEMETRY_NOINSTALL_EXITS, 1);
+    } catch (e) {
+      dump("about:devtools onunload telemetry failed: " + e + "\n");
+    }
+  }
 }, {once: true});

--- a/toolkit/components/telemetry/Histograms.json
+++ b/toolkit/components/telemetry/Histograms.json
@@ -8499,16 +8499,34 @@
   "DEVTOOLS_DEBUGGER_DISPLAY_SOURCE_REMOTE_MS": {
     "record_in_processes": ["main", "content"],
     "expires_in_version": "never",
     "kind": "exponential",
     "high": 10000,
     "n_buckets": 1000,
     "description": "The time (in milliseconds) that it took to display a selected source to the user."
   },
+  "DEVTOOLS_ABOUT_DEVTOOLS_OPENED_KEY": {
+    "record_in_processes": ["main"],
+    "alert_emails": ["dev-developer-tools@lists.mozilla.org", "hkirschner@mozilla.com"],
+    "bug_numbers": [1412029],
+    "expires_in_version": "60",
+    "kind": "categorical",
+    "labels": ["toggleToolbox", "toggleToolboxF12", "inspector", "webconsole", "jsdebugger", "netmonitor", "toggleToolbar", "webide", "browserToolbox", "browserConsole", "responsiveDesignMode", "scratchpad", "styleeditor", "performance", "storage", "dom"],
+    "description": "Records the key shortcut passed to open the about:devtools page."
+  },
+  "DEVTOOLS_ABOUT_DEVTOOLS_OPENED_REASON": {
+    "record_in_processes": ["main"],
+    "alert_emails": ["dev-developer-tools@lists.mozilla.org", "hkirschner@mozilla.com"],
+    "bug_numbers": [1412029],
+    "expires_in_version": "60",
+    "kind": "categorical",
+    "labels": ["KeyShortcut", "SystemMenu", "HamburgerMenu", "ContextMenu", "CommandLine"],
+    "description": "Records the reason for opening the about:devtools page."
+  },
   "MEDIA_RUST_MP4PARSE_SUCCESS": {
     "record_in_processes": ["main", "content"],
     "alert_emails": ["giles@mozilla.com", "kinetik@flim.org"],
     "expires_in_version": "60",
     "kind": "boolean",
     "bug_numbers": [1220885],
     "description": "Whether the rust mp4 demuxer successfully parsed a stream segment."
   },

--- a/toolkit/components/telemetry/Scalars.yaml
+++ b/toolkit/components/telemetry/Scalars.yaml
@@ -916,16 +916,51 @@ devtools:
     kind: uint
     keyed: true
     notification_emails:
       - dev-developer-tools@lists.mozilla.org
     release_channel_collection: opt-out
     record_in_processes:
       - 'main'
 
+devtools.aboutdevtools:
+  opened:
+    bug_numbers:
+      - 1412029
+    description: >
+      Number of times about:devtools was opened.
+    expires: "60"
+    kind: uint
+    notification_emails:
+      - dev-developer-tools@lists.mozilla.org, jdescottes@mozilla.com
+    record_in_processes:
+      - 'main'
+  installed:
+    bug_numbers:
+      - 1412029
+    description: >
+      Number of times devtools were enabled/installed in about:devtools.
+    expires: "60"
+    kind: uint
+    notification_emails:
+      - dev-developer-tools@lists.mozilla.org, jdescottes@mozilla.com
+    record_in_processes:
+      - 'main'
+  noinstall_exits:
+    bug_numbers:
+      - 1412029
+    description: >
+      Number of times the user left about:devtools without enabling devtools.
+    expires: "60"
+    kind: uint
+    notification_emails:
+      - dev-developer-tools@lists.mozilla.org, jdescottes@mozilla.com
+    record_in_processes:
+      - 'main'
+
 navigator.storage:
   estimate_count:
     bug_numbers:
       - 1359708
     description: >
       Number of times navigator.storage.estimate has been used.
     expires: "60"
     kind: uint