How long will a charge last? Does it have a charge indicator?
There is a charging indicator but not a level indicator. With a full charge, expect 6-8 hours of continuous light in the high brightness setting and up to 15 hours in the low brightness setting.
Can this be powered from an external USB power bank for extended run-time?
No. The lantern's internal battery must be recharged for use. It does not operate while being charged.