Network Notify

You're browsing the internet using your mobile data and suddenly you have no signal. It would be great if your phone told you when the signal was back.
Well thats what this app does, you can even choose what kind of network (3G, 4G, etc.) must be available before you're notified.
You can also use it with a quick settings tile, so you don't even have to open the app.
All for free with no ads.