I also hate when apps are doing this, especially when you can't disable it! I really don't know how doing that benefits the user.

Recently I was bit by Instagram app on ios (reported by the client, I am an android user) - it even breaks their own login flow! E.g. You can't open a link from within their app and login to some 3rd party site via Instagram. It simply times out and doesn't even replace the page - thus hides the actual problem. What is worse, is that typical user would blame site developers for this. In the end I had to refactor the flow to avoid login when user is coming from the app...

If you choose to do this, do it this right!