The MSAL library for Android gives your app the ability to begin using the Microsoft Cloud by supporting Microsoft Azure Active Directory and Microsoft Accounts in a converged experience using industry standard OAuth2 and OpenID Connect. The library also supports Azure AD B2C.
A RSS reader library to fetch a RSS feed from the web and parse it to workable objects.
Interesting and fun drop-down refresh library. Do you remember how to play in black and white handheld game it?