ZXDS is an upcoming 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 and TRD/SCL disk files.


+ TR-DOS emulation, allowing loading of TRD/SCL disks (including autoboot).
+ For/next loops in TZX files are now supported.
+ Screenshot support, for SCR/BMP saving and SCR loading.
+ Color/grayscale palette toggle for more nostalgic look.
+ Mode for black and white display of ink/paper only, without attributes.
+ AY ACB and ABC stereo modes and narrow/wide stereo separation.
+ Choice of three relative AY and speaker volume levels.
* Changed AY volume tables to match the real machine more closely.
* Implemented fake low-pass AY filter to avoid aliasing issues in some tunes.
* Fixed setting of AY envelope register even if it doesn’t change, fixes few sound effects.
* Fixed sound clamping when all channels played at full volume and speaker was off.
* Few other subtle changes (initial config autosave, even more safe shutdown).

Thanks to http://www.1emulation.com for the news.