There's no title, it's just the Replies and Likes notifications. The ones you get on your phone when people like your comments or reply to them. When I tried to access the app through it (meaning clicking on the notifications on my phone to open the app, instead of opening it directly by clicking the app icon), the pop-up showed. The pop-up doesn't show if I open the app directly by clicking on its icon (at least for me, not sure about other people)
I've turned the notifications off for now, but this screenshot is from a couple of days ago.
And clicking on 'Cancel' would only give you the pop-up again. Once you get the pop-up, the only way to get rid of it is by clicking on 'Update'. Then of course you'll be directed to the app store while there's nothing to update. Then the only option is to exit it and reopen the app directly from its icon.
Have you guys been able to reproduce it?