I’ve been using uber in the suburbs of Detroit for over a year now, and mostly take short trips. But, from the beginning, I’ve always tipped, and if a driver goes the extra mile to make my day, I’ve tipped more than the actual ride. I have a 4.98 rating as a result. But, I agree that tips should be added through the app. It’s so much easier, as Lyft has had it available for a long time, there is no reasoning that satisfies why not Uber too.