The only issue I had after Lollipop was a random screen flashing loop when I got a SMS/MMS text. Now this issue only happens about ever two or three days and only when I get a few back to back texts. Most of the time it wasn't a issue. First I blamed it on Lollipop but then I changed from Textra to Hangout and no issues. Then I emailed Textra with the issue I had. Then Textra emailed me back it was a Swiftkey keyboard issues that also affects WhatsApp and others Apps. Sometimes it is hard to know what is a OS issue and what is a Third Party App issue.