Heating up while Charging

When batteries are charged, they generate heat normally. As MrBill3 suggests, if the heat makes it too hold to handle the phone, it could be an issue, but that's unlikely. And iPhone has overheat protection built in. If an iPhone becomes too warm, it will display a message on the screen it needs to cool down. Bottom line is charging a phone causes it to get warm and is usually not anything to be concerned about.

Hello,

Start here:

If your iPhone, iPad, or iPod touch gets too hot or too cold

Note: getting warm while charging is normal. If it gets too hot to touch, it should be checked immediately.

Good luck.

Surfing the internet, streaming music etc., all require the battery work and all generate some heat.