This app was mentioned in 1 comment, with an average of 3.00 upvotes
I just downloaded an app to see how accurate it was, and it's pretty accurate. Maybe a degree or two above ambient, but that's about what I expected.
Anyway, wanna see something funny? Check out the reviews for the app I downloaded (which works fine by the way).
https://play.google.com/store/apps/details?id=com.playsimple.roomtemperature