Review on Hangang Pet GPS Tracker: 2nd Generation Anti-Lost Dog Collar with Global GPS/GSM, Waterproof & Long Standby - Track with APP by Jayme Newitt

I was so happy to finally find a pet tracker that does not require monthly maintenance and can accept any GSM SIM card. I have a Google Fi cellular plan that uses T-Mobile and offers only data SIM cards, which are part of the plan at no additional cost. Based on the tracker's description (GSM and T-Mobile SIM recommended) I figured it would be perfect for my needs and I wouldn't have to pay extra as the data-only SIM is part of the existing plan. Unfortunately, this tracker needs its own number and SMS support to activate (or maybe use, I'm not sure). This was a huge disappointment and, frankly, very puzzling as to why the data-only SIM wasn't working. When I inserted the SIM card, after about a minute the tracker successfully picked up a cellular signal and a GPS signal, so it clearly had a service and a location. However, without a number and SMS, you will not be able to connect. Why? It really only needs a cellular signal and GPS to report a location, which it obviously gets, but the app doesn't see the tracker and detailed instructions tell you to text it to make it work. Unfortunately I had to send it back and keep looking for a tracker that works with a data-only SIM card. Unfortunately, if you're using Google Fi or another similar service that only allows data-only SIMs, this won't work for you.