Is Rockstar working on the next handheld GTA?

A trademark filing by Take-Two, the parent company of GTA developers Rockstar, shows something with the name "City Stories" might be on the way.

The listing was registered by Take-Two and covers both "computer and video game programs and software" and "entertainment services, namely, providing online games."

Traditionally, the City Stories moniker was added to handheld games produced in the Grand Theft Auto series, namely GTA: Vice City Stories and GTA: Liberty City Stories. Although as Gamespot notes, it could be the name of an upcoming DLC for GTA 5.

Unfortunately this could also mean Take-Two is just securing rights of the name for future endeavours and might not mean a new game is coming necessarily, but we do know that a Rockstar game is coming in 2015.

Any guesses?