iPhone has in the system great digi wellbeing screen time function.
Learn to control it and use its possibilities to the maximum. Then you won't have to install anything else on your phone.
The guide also includes an overview of alternatives and options on Android.
Why use Screen Time, what it can do and instructions on how to use it, can be found in the short video under the link: https://youtu.be/kl7Gqh-MfVA
With iOS 15 comes a new feature Concentration. I published the instructions on it earlier and you can find it here: https://lukasbarda.cz/navod-na-funkci-soustredeni-v-ios-15/
