Be interesting to see what the capacity of the powerbank is and what affect it has on the light run time.
It will have 1 x 18650 inside, the same as the
common "lipstick" sized power banks, which are generally claimed to be something between 2500 mAh and 3500 mAh, and which charge a phone once.
Mixing uses will be straight arithmetic - charge a phone to full from 50%, and you've got 1h on max or 15h on minimum left for lighting.
(You've obviously got to calibrate your particular phone against it to get realistic answers)
