1. Hold it with two hands high in the air to get a better battery signal
  2. Or for the sun to charge it with its UV rays
  3. Surprise swop it with a stranger and run.
  4. Unplug the power cable feeding the entire stage where Beyonce is currently performing, and use it to charge your phone.
    Cos it's probably uninterrupted power supply and you have to believe how lucky you are then. Also don't forget to run !!! Like really fast...