Simply and casually, the contact lenses exchange date will be announced in the notification bar.

The setting is simply start date to use lenses and notification ON / OFF settings only.
Not using annoying alerts or self-asserted push, we will inform you casually in the notification bar.

Of course, you don't need to keep launching the app.
After setting, even if you close the app, you will be notified on the notification bar on the contact lenses exchange date.