If you spend a lot of time on social networks and other cheap-dopamine, "funny" things on your phone, try grayscale.

There is grayscale on iPhone and Bedtime on Android, perfectly paired with Do Not Disturb/Focus modes.

Personally, I wasn't using Bedtime because of two things:

1. I have a lot of work (job, self-study, writing here, etc.), and I enjoy doing it.

2. Since Nothing OS 2, there is a gray icons mode out of the box and a wallpaper "AI" generator, which makes it easy to generate stylish abstract black and white pictures. So I used it because it just feels nice, especially since I was already aiming for really short screen time.

If grayscale/Bedtime is too tough for you, you may start with scheduling it only for a few hours of focused work, or event just start with a boring wallpaper and monochrome icons.

And remember, there is no "too small time window" for doing or learning something.

I will try it out and let you know if it helps me use this brick even less, because there is still room for improvement.

As reference:
https://www.researchgate.net/publication/340421051_True_colors_Grayscale_setting_reduces_screen_time_in_college_students