Just got my hub and have put it on a USB power meter.
My supply shows 5.03V
Boot up sequence draws up to 0.33A
Inactivity seems to draw 0.24-0.25A
Flic press spikes draw to 0.27A
Connecting the app spikes draw to 0.32A which immediately drops once config is loaded
Connecting to the wired network port brings idle power up to a constant 0.30A
The highest I've seen the Hub draw is 0.37A whilst messing with the app and connected to both wired and wifi
This should help you work out expected run time off a battery, keep in mind battery vendors lie about capacity and they degrade with use too!