Our Traditional devices ( "Edge" vs 'Traditional' GPS Devices ) like the Yabby3 and Oyster3 have full GPS modules and can compute GPS coordinates on board - this enables these devices to be used with all our integration methods - TCP via OEM server, HTTPS JSON via OEM server and Direct TCP.

See here for more info on our Integration Methods Choosing an Integration Strategy 

However, our Edge devices (including the Yabby Edge and Oyster Edge) and the Barra Core use Low Power GPS modules, Wi-Fi Scanning or/and Cell Tower triangulation. These location systems/techniques on our Edge and Core devices are very power efficient however they rely on our Location Engine service (an extension of OEM server) to compute/resolve locations using 3rd party servers and databases. Only HTTPS JSON via Location Engine can be used with the Edge devices. No Direct TCP integration available. 

More info on the Location Engine - The Location Engine - Key Concepts