@KeithD FI Collars look interesting. Definitely a step in the right direction. They use is AT&T LTE-M connectivity. Does this work outside the US?
UPDATE: I found this on their website:
The Fi Collar can only connect to the AT&T network in the United States. Therefore, while abroad, the collar cannot remotely track your dog or provide GPS/LTE updates, such as Live Tracking/Lost Dog Mode notifications.
I believe that they do because they are not dependent on a cell signal. There is a monthly charge for the service. I look after a couple of Ridgeback the owners have purchased FI for them. Even though recall is good, if they get the scent of something who knows how far they will go. Fortunately we have not had use of the service but it gives us peace of mind.
Keith
I bet it does! Thanks for mentioning it here. I hadn’t heard of FI Collars before and am glad to hear tech is racing forward to help our pets. 
@Smiley I bought the air tags when I wanted to start this house sit especially when there were a lot of cases of misplaced luggage at airports. At all time I know where my luggage it. It doesn’t work in South Korea though. They block the signals.