If you have not already noticed, there is a new PSP Emulator out for Android called PPSSPP. It is available on Google Play and sports a 5 star rating with over 1,300 votes which is promising. Here is a excerpt from the marketplace:
PPSSPP is an early prototype PSP emulator for Android and other platforms.
PPSSPP is still in its very early stages and does not run many games. It’s provided here if you want to try it, so that you can automatically receive updates over time – over time this will probably become a usable emulator.
Please go to http://www.ppsspp.org for more information.
I have not tried the emulator yet, but I encourage you download it and give it a try (It’s FREE). Thanks to Bradley White for the update!