Some remarks on current app name "Atomic Clock and Watch Accuracy Toolkit":
toolkit sounds very technical, I would prefer "Tool" or better: nothing => Atomic Clock and Watch Accuracy
Atomic Clock apps are very very numerous in Google Play + the main function of the app is really to measure "Watch Accuracy" => I suggest to reverse the name to Watch Accuracy and Atomic Clock
It will be interesting to also get time from GPS (if no NTP server is reachable / No Wifi nor Data network) => I suggest Watch Accuracy Tool or Watch Accuracy Checker.
Some remarks on current app name "Atomic Clock and Watch Accuracy Toolkit":
What do you think?