I have had technical issues where the app take a little while to end trip or crashes before I end trip. Eithet way if it ran long it is a matter of feet or maybe blocks. If you clearly see on map they rang long definitely ask for a fare review with no hesitation. As an aside that wont affect your rating as we wont see that until well after we have rated you.
So far as tipping I give out plenty of 5s without a tip. For me a tip isn’t expected but always welcome. I may be in the minority in that on this forum. That being said I do believe with Ubers significant fare cuts they should make it easier for customers to have the option to tip via the app.