Paige is holding the solar charger right next to her phone when she is calling her dad to tell him where the chopper flew by them. Although her phone was not charged, it can be clearly seen the solar charged is not connected to the phone while she is making the call.
As the girls are waving down the chopper, they go from kayaks right next to each other in the water to floating a couple of feet apart back to right next to each other.