Fear of losing your pet? no problem
no need to Arduino. many don't know the code of these card. and steps are long is difficult .
what I propose is very easy . you will need a harness for your dog, a waterproof box , foam and a old smartphone.
First, set the box on the harness with two rivets or more.
foam, serve at protecting the smartphone.
1- using your smatphone tracking device in case of loss .
2- you are using the app "follow me" for windows, android and apple
more informations: https://www.followmee.com/