FreeScoreTKD is free and open source software for Sport Poomsae, traditional poomsae, and now Freestyle poomsae scoring on wireless tablets or smartphones.
FreeScoreTKD is designed to run on UNIX or Mac OS X. It can be installed on a Windows computer using Cygwin.
Those who are familiar with UNIX, Perl and Apache should be comfortable installing FreeScoreTKD. There's plenty of documentation online!
FreeScoreTKD is also available as FreeScoreWifi, an integrated wireless appliance using Raspberry Pi; material cost is about $100. Instructions on how to build your own are included in the FreeScoreTKD documentation. If you don't have time to do the installation, you can probably hire a smart high school or college student to put one together for you.