This is done in this function: https://github.com/chrislacy/TweetLanes/blob/master/android/libraries/TweetLanesCore/src/com/tweetlanes/android/core/util/Util.java#L72

Though, it's hard coded text.

That is where the fun starts.  Not all the text in the app is in the strings, some bits were done wrong.
They need to have new string values added and then moved into the strings so you can add the translations.