<b>The versions here don't work with Twitter or identi.ca any more</b>. They only work with GNU Social (formerly StatusNet). You may like to try https://f-droid.org/packages/org.mariotaku.twidere or https://f-droid.org/packages/org.andstatus.app, for Twitter; or https://f-droid.org/packages/org.macno.puma for identi.ca. Mustard is a full-featured client for <a href="http://status.net">Statusnet</a> / GNU Social, a microblogging platform somewhat like Twitter, but decentralized. Note that the hitherto largest Statusnet site, <a href="http://identi.ca">identi.ca</a>, now uses a different platform called <a href="http://pump.io">pump.io</a>. It has many features like attachments, geolocation and avatar update. It supports tags, groups and public timelines, favor/disfavor notices, subscribe/unsubscribe users and multiple accounts. If the server uses OAuth the credentials will need to be put on a server as explained on the website.