my unit is ipod touch 6th gen, 32 gb, purchased just last month here in Saudi Arabia (jarir bookstore), version 9.2.1 (13D15), model MKJ02AB/A. When using waze app (navigator), it has a message in the upper part "No GPS. Showing approximate location"

The iPod Touch models, as well as iPads, have never had an active GPS module.

The iPod Touch 6th gen uses a sort of passive GPS that is designed to pick up Wifi signals from locations that Apple devices detect and automatically report and accumulate this info over time (if you have data reporting enabled on an Apple iDevice or laptop).

That is the extent of the GPS ability on the iPod Touch.

As clarification, iPads that have the optional cellular radio also have GPS like phones do

Yeah,

The passive GPS mode only applies to the WiFi only iPad models.

My bad.