Saw a backpack with a solar panel built in the top to be used for recharging cell phones, tablets and such. Might be worth investigating. But, won’t help much when you’re waaay out in the outback. Suggest a good compass and topographic map; and Bic lighter :)
It’ll work just fine way out in the outback as long as you remember to preload maps. Kind of like remembering to bring along the paper maps. GPS signal is everywhere...as long as nobody shots down the satellites or launches an EMP bomb.