--- a/devtools/client/shared/telemetry.js
+++ b/devtools/client/shared/telemetry.js
@@ -629,16 +629,17 @@ function getChartsFromToolId(id) {
     case "TOOLBOX":
     case "WEBAUDIOEDITOR":
     case "WEBCONSOLE":
     case "WEBIDE":
       timerHist = `DEVTOOLS_${id}_TIME_ACTIVE_SECONDS`;
       countHist = `DEVTOOLS_${id}_OPENED_COUNT`;
       break;
     case "ACCESSIBILITY":
+    case "APPLICATION":
       timerHist = `DEVTOOLS_${id}_TIME_ACTIVE_SECONDS`;
       countScalar = `devtools.${lowerCaseId}.opened_count`;
       break;
     case "ACCESSIBILITY_PICKER":
       timerHist = `DEVTOOLS_${id}_TIME_ACTIVE_SECONDS`;
       countScalar = `devtools.accessibility.picker_used_count`;
       break;
     default:

--- a/toolkit/components/telemetry/Histograms.json
+++ b/toolkit/components/telemetry/Histograms.json
@@ -9528,16 +9528,27 @@
     "kind": "exponential",
     "high": 86400,
     "n_buckets": 100,
     "bug_numbers": [1447302],
     "alert_emails": ["dev-developer-tools@lists.mozilla.org", "yzenevich@mozilla.com"],
     "releaseChannelCollection": "opt-out",
     "description": "How long has the platform accessibility been active (seconds) in accessibility panel."
   },
+  "DEVTOOLS_APPLICATION_TIME_ACTIVE_SECONDS": {
+    "record_in_processes": ["main", "content"],
+    "expires_in_version": "66",
+    "kind": "exponential",
+    "high": 86400,
+    "n_buckets": 100,
+    "bug_numbers": [1451734],
+    "alert_emails": ["dev-developer-tools@lists.mozilla.org", "jdescottes@mozilla.com"],
+    "releaseChannelCollection": "opt-out",
+    "description": "How long has the application panel been active (seconds)."
+  },
   "DEVTOOLS_TOOLBOX_TIME_ACTIVE_SECONDS": {
     "record_in_processes": ["main", "content"],
     "expires_in_version": "never",
     "kind": "exponential",
     "high": 10000000,
     "n_buckets": 100,
     "bug_numbers": [1446496],
     "alert_emails": ["dev-developer-tools@lists.mozilla.org", "jryans@mozilla.com"],

--- a/toolkit/components/telemetry/Scalars.yaml
+++ b/toolkit/components/telemetry/Scalars.yaml
@@ -1135,16 +1135,31 @@ devtools.accessibility:
     kind: uint
     notification_emails:
       - dev-developer-tools@lists.mozilla.org
       - yzenevich@mozilla.com
     release_channel_collection: opt-out
     record_in_processes:
       - 'main'
 
+devtools.application:
+  opened_count:
+    bug_numbers:
+      - 1451734
+    description: >
+      Number of times the DevTools Application panel has been opened.
+    expires: "66"
+    kind: uint
+    notification_emails:
+      - dev-developer-tools@lists.mozilla.org
+      - jdescottes@mozilla.com
+    release_channel_collection: opt-out
+    record_in_processes:
+      - 'main'
+
 devtools.toolbox:
   tabs_reordered:
     bug_numbers:
       - 1456551
     description: >
       Number of times the DevTools tab was reordered.
       Keyed by tab's id.
     expires: "65"