Halfbrick Studios have traditionally been a work-for-hire developer on handheld platforms like the Nintendo Gamoy Advance / DS and Sony PSP, but more recently have made big inroads on developing their own original titles for DLC services like XBox Live, the Apple Appstore, and PSP Minis.
Gamepro.com has an interview with Halfbrick on their current batch of games as well as their thoughts on the current Digital Distribution services. It's well known that the XBox Live Indie Games market place is flooded with a great amount of low-end quality games, with quality titles unfortunately lost in all the noise. Due to that, Halfbrick have no further plans for further titles in that space, and it's a wise decision considering the statistics for XBox Live Indie Games have generally been disappointing for game developers.
Phil Larsen, marketing and community manager at Halfbrick, has had this to say about the other Digital Distribution marketplaces..
PL: PSP Minis are certainly the leader in sales, but we've only just released our first iPhone game and it's been a crazy few weeks. With Sony everything is tightly regulated and built on step-by-step processes, but that does result in a decent space on a established platform like the PlayStation Store. With Apple, everything seems to just fall into place relatively easily, and games are approved quickly.
One of our iPhone games, Blast Off, is a great game but it hasn't really caught on sales-wise. This is probably partially due to the Game Developers Conference recently and the game's short marketing timeframe, but I certainly believe Blast Off still has legs. It's just now starting to climb the charts.
Halfbrick Studios have just released the trailer of their newest iPhone game (coming this month), called Fruit Ninja.