Question: Given the recent "[encouragement](http://techcrunch.com/2014/07/28/facebook-moving-messages/)" by Facebook to migrate to a separate messenger app, and as a followup to the {very informative!} [answer to the question on URL/URI schemes supported by the Facebook app](https://stackoverflow.com/a/5707825/3372061), I've been wondering whether information regarding the Facebook messenger app [custom protocol](https://stackoverflow.com/a/3471554/3372061) of **`fb-messenger://`** is available.

The functionality I was looking for was an ability to click a button that would open a FB-messenger chat windows with the user whose numeric Facebook ID is known. This also needed to work if the Facebook app ([katana](https://play.google.com/store/apps/details?id=com.facebook.katana)) is not installed on the device (i.e. only the messenger, [orca](https://play.google.com/store/apps/details?id=com.facebook.orca)).

I found an [example](https://stackoverflow.com/a/20320386/3372061) of the desired [deep linking](https://developer.android.com/training/app-indexing/deep-linking.html) (`fb-messenger://user-thread/{user-id}`), but that didn't seem to work. I realized that FB has a tendency of revising the URIs every once in a while, since these are generally not supposed to be available to the public (as far as I understand).

Answer: 
With current version Facebook on android automatically ask user to open the app or open in chrome when you use their domain www.messenger.com
It's better to just redirect user to this url and let facebook handle it

<https://www.messenger.com/t/>{username-or-page-name-here}

```
Intent intent;
intent = new Intent(Intent.ACTION_VIEW, Uri.parse("https://www.messenger.com/t/{username-or-page-name-here}"));
startActivity(intent);

```
This simply share a link

```
<a href="fb-messenger://share?link=encodedLink"></a>

```