I'm pretty sure that you would be fine using the charger for your ipad. You can look at the charger to see how much power it is capable of putting out vs. the one that came with your phone. But, I believe that the phone would be able to regulate just how much power it will be taking in so I don't think you have anything to worry about. I personally have not used the charger that came with the Nexus and I have had no problems so far. I have had my phone for about a month now.