PlayTZX has been developed by several authors:

- Created 27/10/1997 by Tero Turtiainen <turtiain@iki.fi>
- Updated to version v0.56b by Tomaz Kac 1998 <tomaz.kac@uni-mb.si>
- Updated to version v0.12c by Philip Kendall 16/05/2005 <pak21-spectrum@srcf.ucam.org>

The license status is currently unknown, but I assume is some kind of freeware with no restrictions.
