Why anyone wanted to unlock their door with their phone instead of tapping a fob, I’m not sure, but the only interesting feature (temp access for friends) doesn’t seem worth it.
I would want to do it with my phone because then I only have to have one thing to carry around with me. I haven't carried a key ring in years. I don't even carry a wallet these days. It's really quite useful. Way fewer trips back to fetch the keys/wallet, etc.
I would prefer this to be a keyring over a phone for aforementioned reasons. Secondly, the app is buggy and often just fails to work. Third, it takes a good deal of time to take out the phone and fumble around with the software.
All in all, it's a pretty miserable experience.
That's my experience of course, other car apps might be much different. But that's an issue with the implementation, not the concept.
Carrying a single thing (which has a bunch of other uses than just access control) doesn't feel like a burden to me.
That said, I don't disagree at all that the typical keypad for access control on everything pretty much sucks. My front door has like 4 buttons only and does the telephone keyboard thing of using the same button for multiple 'numbers' in your code. Time to jump on amazon to look for a decent front door lock that works with my phone :)