Measur is a free app that allows you to track the amount of scrolling you do on Tumblr.

With this app, you can save the distance you scrolled on Tumblr in different amounts. Every time you open the app, you can select the number of pixels, centimetres or metres you want to track.

On the other hand, you can also change the units from imperial to metric and vice versa.

As soon as you start scrolling, you'll start the recording, and the distance will be stored for the next visit.

If you don't want to have all your Tumbles recorded, you can always delete all the previous recordings or choose to stop recording whenever you want.

Finally, you can also check your total and see how much you have recorded.