Cost: Free and Premium edition
If you have ADHD, then you know how important it is to improve your awareness of time. RescueTime allows you to see how you are spending your time on your computer, because if you want to save time you need to know how you are spending time.
RescueTime runs in the background and tracks your online activity. When you review your activity, including the two hours you spend watching cat videos, you can rate the activity from "very distracting" to "very productive". You can then set goals and track your progress.
There is a free version which allows you to track time in websites and applications, and there is a premium version which will also allow you to block distracting websites. For example, if you only want to spend 30 minutes a day on Facebook, it will block Facebook after half an hour.
Easy to use
Great way to set goals to monitor time spent on devices
Website blocker only comes with the Premium version
Available for: Mac, PC, Android, Linux