Originally Posted by
TiHabanero
I'm surprised rim dynamos have not been mentioned yet. Pedalcell and Velological are two that I know of. These are not like the old 3v systems of the 60's and 70's, but are modern efficient dynamos that don't cost a fortune and are relatively lightweight and will solve your charging needs with ease. Easy to install and don't require a dedicated wheel to use them.
Post 4 did but IME people looking to charge their phone aren't looking to spend the money on the dynamo and cache battery USB charger. My Cinq's were ~250 euro each, and dynamo hubs are 100-300 depending then there's the wheel build/rebuild.