For the first time, Shin Megami Tensei IV will be a main numbered title for a handheld console. Yamai talked about their reason for going portable.
Actually, nobody from our development staff felt that it was required to make a main numbered title on a non-handheld console, Yamai says. If anything, we believe that handhelds are perfect for RPGs that involve character growth. For example, you can try fusing some demons before going to bed and fall asleep after making one that satisfies you, or test out any demons you made.
You can open it whenever and simply put it in sleep mode when you close it. I believe that handheld consoles allow you to enjoy it in this lighthearted way.