Toolkit Pro is an all-in-one app featuring all the essential tools you need  - The indispensable application for your Windows Phone
 

16 main tools in this version:
● Ruler, Compass, Protractor, Level
● Flashlight, QR code, Vibrate, Quick settings
● Unit converter, Currencies
● Noise meter, Recorder
● Timer, Stopwatch, World clock, Speed meter

 

Free version:

Paid version:
http://windowsphone.com/s?appid=f54c6c1e-80e5-4575-a41d-0fd323eae1ee