A free program for Android, by mydroid.

Fake Call, Fake Caller ID, and GF Fake Call is a prank calling app that allows you to make prank calls to your friends. The app has many different numbers that you can choose from, so you can call your friends with different names. It can be used without the internet or Wi-Fi, so it’s easy to use and doesn’t require any additional hardware. You can even make calls from your Android device to your iPhone or Android phone, or vice versa.

This app is a great way to have some fun and to get out of an awkward situation, like a boring meeting or an uncomfortable conversation. It can also be used to prank your friends and family to show them that you are not in the phone number that they think you are.