Writing polished Android apps is difficult. At Square, we've promoted lots of code from internal-only to open source. Some parts of the process:
Scope
Our best projects address one problem only, and address it completely.
API
We make lots of little touches & tweaks. For example, with Android FEST we changed the package name to be consistent the Guava and Joda Time extensions.
Name
We like clever names like Otto and Tape.
Today Jake Wharton promoted JavaWriter to Square's open source tool box. It's a humble tool for generating code. No templates and no ASTs!
See Square's open source projects on GitHub.
