The output on the OEM charger is 5V at 1.0A. Would it be safe to use my 2.0A at 5V iPad charger with the phone? I don't want to carry around two USB chargers if possible. I imagine the charging circuitry on the phone wouldn't provide it with excess current but wanted to be sure. I did it for a few minutes and it seems to work fine but just wanted to make sure.