sz81 v2.1-5-1 Open2x is released. sz81 is a Sinclair ZX80/ZX81 emulator very much based upon the work of Ian Collier's xz80 and Russell Marks's z81 but employing the highly portable SDL and including additional functionality and features for desktop computers and portable devices.

Features (not GP2X specific):
- Virtual keyboard with adjustable opacity, autohide on newline, sticky shift or toggle shift
- Control bar with access to several regularly used options
- Full mouse/stylus and joystick support throughout
- Runtime joystick control remapping
- The ability to run centred within any resolution
- Runtime switchable scaling up to 3x on supported platforms
- Toggling between a window and fullscreen on supported platforms
- Support for portrait orientated screens such as 240x320 and 480x640
- Maximum porting potential since it only requires SDL

Download: sz81 v2.1-5-1 Open2x
Source:Here