Inertial dampeners

I'm not replying to what you think I'm replying. To summarize: little plastic arms are not useful against dropping a phone from 150 ft. Because: 1. they are not made to absorb a shock that large, 2. even if, the phone would bounce, 3. even then, you're looking for a phone in a fairly large area. Easier not to drop it all of 150 ft in the first place; most people dropping phones do so from human-comparable heights, and that's where the little plastic arms are useful.

Clearer now?

Aha, that is indeed one thing I haven't thought of (amongst many others, I'm sure).