The solar panel does not hold a charge it produces power when it is exposed to sunlight. You can plug your phone directly into the panel or use it to recharge a portable recharger for later use. The Nomad 7 is best used for recharging things like:

Headlamps
Phones
Other smaller USB devices
Goal Zero USB Power Banks

Nomad 7 panel works best with all of our small rechargers.

Switch 10 Core 4-6 Hours
Flip 10 Power Bank 2.5-5 Hours
Guide 10 Plus Power Bank 3-6 Hours
Flip 20 Power Bank 4 Hours
Venture 30 / Flip 30 Power Bank 8-16 Hours