IPView is a small application which displays the current local and public IP address of your android device and offers a widget for quick checks (updated every 15 minutes or when you tap it).

• The first box is local IP, which is the IP address that the iphone will receive from either the mobile or WIFI network.
• Then the public IP, which is the IP address that the iphone presents to the outside world. It can be the same as the cellular IP, Wifi IP or an entirely different address depending on whether your cellphone provider or WIFI network uses NAT.
• The final box are the reverse DNS hostname of your main IP address.

You can download ipview from the app store.