SchemingMind implements XFCC Basic protocol. Thanks to it, it is possible to write applications, which connect to the site, download games list, and let players make moves.
At the moment XFCC does not handle most of the variants.
Desktop chess apps
A couple of desktop chess applications can be used to view SchemingMind games and make moves:
XFCC protocol
XFCC is an open protocol (developed by Martin Bennedik, the author of the ICCF webserver), so any interested developer may create applications using XFCC without any licencing implications.
Suggestions for development have included printing software (possibly combining XFCC with LaTeX) to make high quality printouts of games possible from a desktop client. Maybe another idea would be an XFCC Screensaver.
In addition to SchemingMind, XFCC is supported by the ICCF server and also by the German CC server, mychess.de.