diff --git a/README.md b/README.md
index 5176fe729c..64740d3206 100755
--- a/README.md
+++ b/README.md
@@ -60,6 +60,7 @@ List of Definitions
 * [File API: Writer](http://www.w3.org/TR/file-writer-api/) (by [Kon](http://phyzkit.net/))
 * [Finite State Machine](https://github.com/jakesgordon/javascript-state-machine) (by [Boris Yankov](https://github.com/borisyankov))
 * [Firebase](https://www.firebase.com/docs/javascript/firebase) (by [Vincent Bortone](https://github.com/vbortone))
+* [Firefox](https://developer.mozilla.org/en-US/docs/Web/API) (by [vvakame](https://github.com/vvakame))
 * [FlexSlider](http://www.woothemes.com/flexslider/) (by [Diullei Gomes](https://github.com/Diullei))
 * [Foundation](http://foundation.zurb.com/) (by [Boris Yankov](https://github.com/borisyankov))
 * [FPSMeter](http://darsa.in/fpsmeter/) (by [Aaron Lampros](https://github.com/alampros))
diff --git a/firefox/firefox-test.ts b/firefox/firefox-test.ts
new file mode 100644
index 0000000000..30f7d7493c
--- /dev/null
+++ b/firefox/firefox-test.ts
@@ -0,0 +1,28 @@
+/// <reference path="firefox.d.ts" />
+
+var manifestUrl = window.location.protocol + "//" + window.location.host + "/manifest.webapp";
+
+var log = (data:any) => {
+	alert(data);
+};
+
+var setupCallback = (src:string, request:DOMRequest<App>) => {
+	request.onsuccess = (data)=> {
+		if (request.result && request.result.manifest) {
+			log('app is installed ' + request.result.manifest.name + " by " + src);
+		} else if (request.result) {
+			// bug 806597. https://bugzilla.mozilla.org/show_bug.cgi?id=806597
+			log("app is installed by " + src);
+		} else {
+			log("app is not installed by " + src);
+		}
+	};
+	request.onerror = ()=> {
+		log('failed, error: ' + request.error.name + " by " + src);
+	};
+};
+
+var apps = navigator.mozApps;
+setupCallback("install", apps.install(manifestUrl));
+setupCallback("checkInstalled", apps.checkInstalled(manifestUrl));
+setupCallback("getSelf", apps.getSelf());
diff --git a/firefox/firefox.d.ts b/firefox/firefox.d.ts
new file mode 100644
index 0000000000..dd052f1a8f
--- /dev/null
+++ b/firefox/firefox.d.ts
@@ -0,0 +1,39 @@
+// Type definitions for Mozilla Web API
+// Project: https://developer.mozilla.org/en-US/docs/Web/API
+// Definitions by: vvakame <https://github.com/vvakame/>
+// Definitions: https://github.com/borisyankov/DefinitelyTyped
+
+// required lib.d.ts
+
+// expand Navigator definietion.
+interface Navigator {
+	mozApps:Apps;
+}
+
+interface Apps {
+	install(url:string, receipts?:any[]):DOMRequest<App>;
+	getSelf():DOMRequest<App>;
+	getInstalled():DOMRequest<App[]>;
+	checkInstalled(url:string): DOMRequest<App>;
+}
+
+interface DOMRequest<T> {
+	onsuccess: Function;
+	onerror: Function;
+	readyState:string; // "done" or "pending"
+	result:T;
+	error:DOMError;
+}
+
+interface App {
+	manifest:any;
+	manifestURL:string;
+	origin:string;
+	installOrigin:string;
+	installTime:number;
+	receipts:any[];
+
+	launch();
+	checkForUpdate():DOMRequest<any>;
+}
+