PPSSPP is a PSP emulator that can run games full HD resolution. It can even upscale textures that would otherwise be too blurry as they were made for the small screen of the original PSP.
What's new in 1.11.3:
What's new in 1.11.2:
What's new in 1.11.1:
What's new in 1.11.0:
Fix various crashes.
What's new in 1.6
1.5 has support for Vulkan, the new faster way to draw graphics. Supported on many modern Android devices, and if enabled (change Backend in Graphics settings) you will see a massive speed boost. PPSSPP 1.5 also has the usual assortment of fixes: