If this turns out as planned they could (possibly) go deeper than submarines and see deep water life! Why? Smaller mass. Subs are giant and need oxygen to keep the people alive, but if it's a small drone, without needing an oxygen supplie with not mutch mass could go pretty deep. But it needs to be really compressed. And I suppose it needs a camera but it could be solar powered. Power up in the sun while going down, then when it gets to the twilight zone it would resive less power and when it's to deep to power its self, use the energy! I don't know if this can be done or I'm right, this is just my inner little boy speaking. But I personnely think it can be done.