Also, it wouldn't be a bad gift idea for someone who would otherwise carry nothing at all. Just show 'em how to use it as an old skool 'church key!' We still have something to teach those young whippersnappers. Lots of those gorgeous microbrews use non-screw-top bottles. And no, kiddo, there isn't an app for that.
Improvised "Church Key" that brings back memories, how else did guys like us open stubbies at a bush party back in the "70's.
That is what the latch mechanism on a car door is for. . . .