Are freemium games evil? That was the stark question in the Indie Day of the Develop Conference.

"Some companies have been borderline predatory in terms getting gamers to buy in-game items," argued Tracy Erickson, of Unity (previously of Pocket Gamer).

"Some are using the business model to manipulate gamers to buy items. And I think the vast majority of them have been bad games too."

However, he said he didn't think that it had to be that way. "The business model is amoral; it depends how you use it. There needs to be a creative aspect."

In this context, James Parker, of Mobile Pie, pointed to NimbleBit's Tiny Tower as a game with a 'soft touch' in terms of not forcing players to buy items.

"I think we're in a growing phase," said Dan Keegan, from OpenFeint. "But I think freemium is the end game. I'd encourage everyone to make freemium games."

Jas Purewal, a game lawyer at Osborne Clarke, pointed to some deeper issues.

"Free is powering some tensions in the industry. Players think they own the items they buy in these games, but what happens if a game is shut down? These points aren't clear yet."

"People have always paid to progress quicker in games in terms of buying a Prima guide or upgrading their PC," Parker pointed out.

"Freemium's different though," replied Erickson. "If it was completely optional to buy items, I don't think we would be having this discussion,"