ZXDS is an emulator of Sinclair ZX Spectrum for Nintendo DS, written by Patrik Rak. It is steadily reaching a mature stage of development, and it already has some noteworthy features, like accurate emulation of Spectrum 48k, 128k and Pentagon models (including sound), or support for TAP/TZX/PZX tape files, TRD/SCL disk files and RZX playback files.

Changelog:
Tweaked RZX code to work with more nonconformant but commonly available recordings.
* Worked around sound clamping while keeping the sound loud by throwing dummy sample into the mix.
I knew there must have been a reason why I didn't use sound bias 0 alone long time ago.