I recently received following email for one of my Android app which is using share on facebook feature. Unfortunately it wasn’t clear from this email what policy my app has broken. So I replied to facebook asking to explain it further and they did. It turns out that share on facebook feature wasn’t showing thumbnail and details. They were also helpful to create a video and show what was wrong.

I’ve fixed this issue and hopefully it will satisfy them.

Hi,

In working to create a great Platform experience for everyone, we ask developers to ensure the apps they build comply with our Platform Policies. Your app ***  (AppId: ***) doesn’t comply with the following:

Platform Policy 1.2: Build an app that is stable and easily navigable. Be sure your app insights reflect a positive experience.

Here’s a visual example of the policy: https://developers.facebook.com/policy#1-1-photo. 
Some common violations of this policy include:
– Broken Facebook integration (e.g. broken login or canvas integration)
– Broken functionality in the app (e.g. share functionality is broken)

You can access the full list of our Platform Policies here: https://developers.facebook.com/policy/.

Please make the requested changes by *** at 12:00 PST.

Let us know when you’ve updated your app by replying to this email. If we do not hear back from you, your app will be subject to enforcement. If you have outstanding questions, respond here and we’ll do our best to help. 

Thanks,

***