That's one way of seeing it... Usually when I am at work or work with my Mac most likely my phone is either with some decent battery % or being charged. So if I leave for a few min, my phone usually always goes with me thus will work fine without another device.

I just scan around and there is another app in the Mac AppStore: https://itunes.apple.com/us/app/keycard/id578513438?mt=12

And some tutorial: http://mac.tutsplus.com/tutorials/security/use-your-phone-to...

which reference another open source project -which seems left in the water for the past few years.

Anyway the concept overall is good but I think I am not the target market: not really interested to add one more BT devices that I need to carry.

Good luck to the team