Sony doesn't see any clear competitor for its PlayStation Portable successor, codenamed the Next Generation Portable.

Why? Because it's so unique.

"There's no one clear competitor in terms of what NGP offers," Shuhei Yoshida, president of Sony Computer Entertainment worldwide studios, told Eurogamer in an interview.

"NGP's going to establish itself as the unique thing that people want to have. NGP cannot be placed against smartphones. You can't make phone calls on it and it's too big to fit into your pocket."

NGP, rumoured to be officially called the PS Vita, features dual analog sticks and a five inch OLED touchscreen.

Some commentators have suggested it's set to go head-to-head with Nintendo's 3DS when it launches later this year, but Sony doesn't see it that way.

"Compared to 3DS, it was very interesting when we were designing the NGP we had no idea what Nintendo was going to do," Yoshida revealed.

"Aside from the 3D stereoscopic display, they seem to be keeping the same theme that they had with the DS it feels like an update of the DS to me.

"Lots of choices we made were so different from their choices. It's kind of hard to compare the two, aside from the fact that both of them are dedicated gaming platforms."

But Yoshida said Sony and Nintendo had a common enemy: the cheap mobile game.

"We are dealing with the same issue that Nintendo is. It's up to content publishers, including ourselves, to show people that this is worth 25 or 30 as opposed to 59p.

"You cannot release the same content that you put on the iPhone for a dollar on to NGP or some other consoles and expect people to pay 20 times that."