I'm using a dyno and either a LuxosU or an Exposure Revo with USBwerk. I also carry a small auxiliary battery.
Last 2 days did an overnight and got to camp with a full GoPro after shooting video off and on during the 6 hour ride. Ran the battery down to halfway after shooting a timelapse last night. Charged off and in today due to the climbing and shot another 1.5 hours of video. Battery was at half when I got home - so I was putting in what it was using.

For my phone - I usually keep it off or in airplane mode and top off at night with the auxiliary battery (which I can also charge from the dyno).