The Apple Watch Series 3 was announced on 12th September 2017 and released that same month. It had the same make and look like the Apple Watch before it, series 2.
The biggest change, of course, was the fact it was the first Apple Watch that could support LTE. This was a major improvement from previous apple watches before it. It features an LTE and UMTS cellular radio which would automatically switch to cellular if you happen to be away from the companion iPhone.
It has an electronic SIM or eSIM which has been said to be one per cent of the size of a traditional SIM, with the display acting as the antenna, both the transmitting and receiving element. This Apple Watch 3 is compatible to iPhone 6+ or later models.
How much memory does Apple Watch 3 have?
The Apple Watch 3 is available in variants of 16GB 768MB RAM and also 8GB. Depending on the type of model you buy, and the memory space you will have access to. In case, you desire an Apple Watch with a bigger memory space, then at 32GB of storage for both GPS and Cellular models, the Apple Watch Series 5 offers double the storage of the previous Series 4 models, and should be your choice.