It's super simple and completely free app that let's you easily track work time and automatically calculates break time based on flowtime technique.
You can access the app at the following link: https://flowtime.streamlit.app/
It's an alternative for pomodoro technique, where you work for 25 minutes and take 5 minute breaks. With the flowtime technique, your work intervals and breaks are not scheduled. You simply work until you’re distracted or until you feel like you need a break. It allows you to stay focused longer and get into the flow state.
It's 20% of the time you've been working for. It's that simple! So if you need to take a break after 25 minutes you will have a 5 minute break - just like in Pomodoro technique. Alternatively, if you get distracted after 10 minutes, you will have a 2 minute break. However in case you went full on into a flow state and managed to keep focused for whole 90 minutes, you will get an 18 minute break! That's why I think the flowtime technique is a better and more flexible alternative to the pomodoro technique.