picks up where Photo Measures leaves off. Unlike Photo Measures, Measured aims to be a total replacement for your tape measure.

The app uses your iPhone’s accelerometer to measure distances and dimensions without the need for a tape measure. Launch the app and you are greeted with a tutorial that walks you through the calibration process. First, you need to specify what kind of shoes you are wearing and what size. This is so the app can accurately determine how long your steps are—you must do this every time you wear a different pair of shoes when using the app. (Alternatively, if you want to be extra precise, you have the option of measuring your own shoe and manually entering the length.)

Next, you need to calibrate your iPhone’s accelerometer by tapping the Level button, placing it against a doorframe, and rotating it twice. A video tutorial demonstrates the process, which is essential to getting accurate measurements. After the calibration is complete, you’re ready to start measuring.

Measuring is a little complicated at first, but the process gets easier once you get the hang of it. First, you take a photo of the object you want to measure. Then, you carefully step heel-to-toe at least one-third of the distance to that object, remembering to set a step-count (the default is six but I found 2 or 3 was usually sufficient) before taking another photo.