Gundam Assault Survive, which Amazon Japan has in their database, might be the next portable Gundam title. The retail listing is the only mention of Gundam Assault Survive since it hasn’t been officially announced. However, the game may be coming soon. Amazon’s listing says Gundam Assault Survive is slated for release on March 18.
Update: Looks like this is going down. On top of the Amazon listing we searched the Japanese trademark database and discovered Namco Bandai registered the rights to Assault Survive.