Requires MacOS Yosemite 10.10 or newer
Get RescueTime for a different operating system
Note for Firefox users: To accurately record websites in Firefox, you should install the RescueTime Add-on.
Open the file 'RescueTimeInstaller.pkg' and follow the instructions.
(It's probably in your downloads folder)
After installing, sign in to the RescueTime app from your menu bar.