Data on a Phone Call

There's probably an app for that.

or, Sensatronics Temperature Monitors: may have something that will work.

Look at weather stations.

I bought a simple weather station and installed it in our house in Minnesota (we're never there) The neighbor across the street can monitor the temperature inside our house and call me (in Arizona) if there's a problem.

Got a neighbor?

I looked at the Apple Store and I couldn't find a "Neighbor" App.