Uses of decreasing usefulness (for me): 1) it helps me not to miss calls (when the laptop is at the bottom of the backpack or placed somewhere) because the watch vibrates (call, SMS c ... ' is easily configurable). 2) trigger pictures remotely and voice memos is convenient (improved selfies) 3) check in 3 seconds malls so handy 4) make the phone ring I happen to find it once every other day 5 ) embedded calculator 6) the rest: Photo of telephone, alarm clock, torch, ... and time. A total of 3 screens 6 apps and that's enough.
I wondered if he had no internal storage (music, files, etc.): in fact the answer is no because the phone is stuffed.
Autonomy is OK (all three days)
The screen is not "retina" (we see the pixels a bit), but trans-thing: sunlight readable.
Finally: the price is really good: 100 euros, it was worth the money and it's not like Apple disproportionate Watch (400 euros seems delusional properly).
Sincerely,