Can I change my goal later?

Yes. Tap a goal to open its detail screen, tap the three-dots menu in the top right, then select Edit. You can change the title, reminder times, when to be reminded to do the goal (e.g., 30 min before your reminder time), when to be asked to check in (at reminder time or X minutes after your last reminder), and why statement. Note: If you've completed at least one check-in, frequency (daily vs weekly, number of days) cannot be changed to prevent streak manipulation.