Google Androidify

Google Androidify was born out of the spirit of the Android operating system—a system that lets anyone make, build, offer or buy all sorts of things, but in a way that helps all those things work together. Even the Android mascot is open source. Sadly, Androidify shutdown in 2020.

Official description
Androidify yourself!

Create, accessorize and share Android characters that look like you, your best friend, your Uncle Sal—anyone, really.

Create and share your animated Android characters as emoticons, animated GIFs and pictures over texts, posts or chats.

Be sure to submit your creations online, where you can share to the Androidify.com Gallery to hang with Android characters from around the World.