Click the timer/clock icon above the play button. Double click and highlight the time, then delete and enter your new time to adjust the timer to your desired focus session length. You may enter an amount of time from 1-240 minutes. You must set a minimum of 20 minutes to enable the productivity tracker (this is an optional feature)
The timer will return to the set time of your session once the session is completed. If you edit the timer during a session, it will stop that session and allow you to enter a new time, or start a new session with the previously saved time amount.