J-LINK EDU Mini (8.08.91), made by Segger company, is a reduced form factor of J-Link EDU (very popular JTAG/SWD Emulator) with identical functionality for Cortex-M based targets. It has been designed to allow students and educational facilities as well as hobbyists access to top of the line debug probe technology. It runs on Windows, Linux and Mac OS X.
J-LINK EDU Mini is very well supported, every legitimate owner of a SEGGER J-Link can always download the latest software free of charge. This little board provides a lot of possibilities in a very good price and best quality.