Similar here. I use the app since it doesn't do anything invasive, but I also have a paper backup (I don't always carry it) because it's a bit too important to

Similar here. I use the app since it doesn't do anything invasive, but I also have a paper backup (I don't always carry it) because it's a bit too important to be dependent on a phone only. I bet I'd first find out about my certificate being revoked at some check point where my phone isn't working and I can't easily get a new one...