It doesn't sound like you've ever seen a crash. If the phone is on the pocket it can easily get separated from the ride before the rider feels a strong impact.

It doesn't sound like you've ever seen a crash. If the phone is on the pocket it can easily get separated from the ride before the rider feels a strong impact. I'm not sure how you think the phone should figure out if it is disconnected from the bike. While it may be possible to improve crash detection. I don't think any of your suggestions come close. And generally will make things worse