Question

I am developing the application by Facebook PHP SDK.
If a user uninstalls this application from the Facebook page, I’m going to delete related data from my app. Is there any way of recognizing uninstallation of an application by PHP?

Answer 1

From the docs on authentication:

App Deauthorization

When a user of your app removes it in the App Dashboard or blocks the
app in the News Feed, your app can be notified by specifying a
Deauthorize Callback URL in the Developer App. During app removal we
will send an HTTP POST request containing a single parameter,
signed_request, which contains the user id (UID) of the user that just
removed your app. You will not receive an user access token in this
request and all existing user access tokens will be automatically
expired.