Used this with moving from a Pixel 3a to iPhone 12 and it was pretty terrible. Anytime the iPhone screen timed out, the app would show a failure. This was after 10 attempts of trying different transfer categories. The best solution was to set my Google phone to 30 minute screen timeout and tap the iPhone screen every minute to keep it awake. After 20 minutes the iPhone timed out & thought I was doomed. I finished the iPhone setup and there was multiple issues but most of the stuff was there!