[Xperia Play Themes and Apps] Drakonas:
Besides, emulating any same gen system takes much more power than running a PSP game on a PSP. When you emulate a game from another system, you have to "emulate" the hardware of that system WHILE the game is running. This is much too powerful for even some dual-core GPU/CPU phones out there. (Maybe the Tegra 3 will be able to do it)

Here comes a long synopsis. If you want the short version, scroll down.

The fact that a system, say a PSP, has better graphics than a system, say a DS, you want it to emulate does not mean it is easy for a PSP to emulate a DS. (touchscreen problem aside here, just using an example)

Not only that, but say you wanted to try and optimize an engine to run a DS game on a dual-core phone.

You have two options:

1. Make it look as accurate as possible to the original DS, in the meanwhile having very laggy framerate (this is how most emulators start out, I think, like nds4droid).

2. You can have your emulator cut down the polygon count (meaning simplify the graphics so the graphics processor isn't "processing" so much), so that you can reach your goal of a substantial framerate. Even though this is the route emulators

should

take, it is also the hardest on both the team/developer to make it happen.

It takes ages to get an emulator to run smooth, because most games are designed differently on the "behind-the-scenes" side of the game, or the code. Once your engine is finished, and it runs games like Mario Kart 64 near to perfection, you soon realize that other games aren't "compatible" with your emulator. Some games won't boot, others have graphics, audio, or controller problems. This means you now have to add "patches" to your emulator.

And the more patches you add, the slower the emulator starts to get, and the higher the demand for more powerful hardware (graphics chips/cards and processors, specifically). Look at how the development of PCSX2 has been going the past year. I used to be able to run Kingdom Hearts II at the original framerate with my dual GTX 280s. Now, with the updated emulator and the same settings, it lags quite a bit because they've added so much to the engine.

Long story short:

Making an emulator takes time and teamwork. Some teams get stressed, and aren't willing to continue development, whether it be hardware limits or not enough willpower.

Emulating a game system takes a lot more power than running a game native to that system. The system has to emulate the hardware AND software (game + "operating system" running the game) of the other, WHILE still running its own operating system (Android is still running while the emulator is running, which can slow down performance).

My ending statement:

I think a DS Emulator for Android with good framerate IS possible, even on some 1GHz dual-core phones, but it will require 2 things:

1. A dedicated team that has some smart programmers and good team-leadership (so that things get done).

2. An Android rom for your phone that is light on resources, so as to not slow down performance. I use Neutrino EE for my Motorola Atrix 4G, and it's faster than any Android I've ever seen. Any app opens in milliseconds after tapping the icon. It's also 3 times as small, compared to most roms on the Atrix. (50MB vs. ~150MB)