Stanley Smart Measure Pro

Stanley Smart Measure Pro is a smart tool that attaches behind the phone and connects to it via Bluetooth.
After the calibration of the laser, which takes about ten minutes, you get access to 2 measurement options:

• Straight line laser measure.
• Software that uses an image to measure the total square metres of surface area. Available for iOS and Android.

Pros:

• Don't need to write measurements;
• Very accurate;
• See the measurements directly on the phone screen;
• Can export the measurements in PDF and JPG;
• Measurements up to 137 m
• Affordable price: $127.99

Cons:

• Can't freeze the measurement on the screen.
• Inside can't get the correct distance because have to look at the screen to read the measurement, so it can't measure the space behind you.