You should be ok, emphasis on should. Most USB devices require 5 volts for power, and most USB ports put out, you guessed it, 5 volts. I would be cautious though and stick with only the charging cable that the phone manufacturer provided. Some USB devices may only require 3 volts, and their chargers will have a resistor built into them that reduces the voltage to that, and if you provide too much voltage you may damage your phone. So my 2 cents, be careful!