Definitely keeping an eye on this thread. I haven't been out on trail long enough on any single trip to really need to consider solar. The battery pack method has worked quite well though...
http://www.amazon.com/Jackery-Portable- ... ikearizona
One of those kept my headlamp (Petzl Tikka RXP), InReach SE (10min beacon, lotsa messaging in both directions, bluetooth on,) and Galaxy S5 phone (Gaia maps, GPS on, bluetooth on to control the InReach/messaging) with about half a charge remaining for 4 days in the blue range. Phone also served as a ghetto jukebox on a couple nights of drinking by the fire.
I'd imagine even a less beefy solar setup could extend that significantly by having it keep the battery pack topped off.