Ok I am not sure if this is an april fools joke, but i was just browsing and i came across this: http://www.gamestrend.de/articles/v/49a8bfb3-a41a-4468-af71-d8b336eb6353/Grand-Theft-Auto--Red-Sun---Fuer-die-PS-Vita-in-Entwicklung
Using Google Translate it reads:
Grand Theft Auto: Red Sun - in development for the PS Vita
01.04.2013 - 08:44
Rockstar North has told us in an exclusive interview that you have a new part of the series for the Playstation Vita in the development.
In an exclusive interview with Dan Houser of Rockstar North, we can learn as a first game portal, which is currently a first Grand Theft Auto spin-off for the Playstation Vita in the development. It is called Grand Theft Auto: Red Sun. Here are the first info-bites:
As the name suggests, it will be in the land of the rising sun, Japan settled. You play the criminals Maeko Michiko, because of his family history came as a small child with organized crime, the Red Sun Group, in contact. When one day he will sell at a deal of his own chief of police, begins the story of Grand Theft Auto: Red Sun.
The scope of the title should be about the same as it did in Grand Theft Auto IV (only the main game). In addition, we wanted to use all the control options Vita, both in the regular game as well as in the mini games such as darts or billiards. When exactly Grand Theft Auto: Red Sun appear on the Playstation Vita could not be said. Period as we have been called simply the fiscal year 2015.
For more information and pictures of the meeting with Dan Houser at Rockstar North, follow the News special this week.
Source: Interview with Dan Houser / Rockstar North
Again i am not sure if this is an april fools joke.