We're thinking about it. The thing is, it needs to be free-to-play
Yeah, that's a good point - F2P models are trickier than people think. You could just make it run in "no save mode" or something, but you need to occasionally remind people that they can buy the app.
I've heard good reports from people that use a "robotic haggler" system. For instance, Dub Wars has it set up so you can check the buy page and it'll say the game is $15... but if you cancel, and don't buy, it'll say "Wait, before you go! We're gonna offer you a one time-deal. Buy the game right now for $10. If you cancel, though, this deal's gone for good!" Something like that.
I'm guessing there should be different modes for touch emulation. Using the trackpad is usually NOT what you want. Maybe there could be a mouse mode (as well as the ability to use an external mouse..) that has a visible pointer on the screen.
Visible mouse pointer would work pretty well for a lot of games, and I think Android is capable of making that happen pretty simply. You're just not gonna be able to play, say, Elite Beat Agents very well. That's not the end of the world, though. There are a ton of great DS games that don't rely heavily on the touchpad, so DS emulation is still a great value. It's the same on phones, after all - not every game plays well without physical controls, so users just have to make good game choices. In the end, a gamepad just isn't the best input device for all DS games.
But if that's the only problem, there's a solution - let people use other input devices. I know OUYA supports mice pretty well, so hopefully mouse support should be simple. If you wanted to do something really cool, though, you could let people use Android devices for input! Sorta like the Wii U. You Don't Know Jack for OUYA does this right now and it's really cool. The way it works is that users download an app onto their Android device, then connect it to the OUYA over bluetooth.
But that'd be a ton of work for such a small audience. Or... I guess instead of making a new app, you could build that functionality into the current DraStic port?