How can I change the glow interval frequency?

The main view in the app is the volume of water you drank, but you can switch to the intervals graph which tells you about the frequency of drinking during the day. You can set the glow reminders to 30 or 60 minutes, and the intervals graph is related to your settings.

If the dot is colored, that means you drank, if not you did not. Also, if you forget to drink between intervals, the bottle will remind you with a glow. The goal is that you not only drink enough water but also that your drinking is evenly distributed during the day.