What it can do?
Almost nothing actually. It uses an API to make a JSON request and display how it went. It can do so automatically every X seconds and it handles various error situations. User can trigger another test to skip the waiting period.
Why would you want it?
You wouldn't. Unless you are really crazy geek and want to see your IP address displayed on your watch. Or you have a trouble with some other widget unable to connect to the phone or network, and you would like to check if the problem is global.
How to get it?