Any GPS that supports the NMEA standard data format,  which is to say virtually every GPS on the market*, should work.  GlassView supports connections via Bluetooth (wireless), USB and serial (COM).   We have tested options available to you, by contacting Sales@seattleavionics.com.  Unfortunately we do not have the ability to test all brands and models.  * Units connected via a USB cable may need an appropriate USB-Serial driver available from most manufacturers.  Some new Garmin units, such as the 396 and 496, may require a very inexpensive software 'bridge'.  Contact Sales for further questions.