OnePlus Zen Mode is described as 'Zen Mode will help you put down your phone and enjoy your life. Schedule a time and then start Zen Mode. During this time you can better focus on current things without disturbance from the phone'. There are more than 10 alternatives to OnePlus Zen Mode for a variety of platforms, including Android, iPhone, Mac, Windows and Linux. The best alternative is Cold Turkey, which is free. Other great apps like OnePlus Zen Mode are Forest (Freemium), App Usage - Manage/Track Usage (Freemium), Offtime (Freemium) and iChooseTo (Freemium).
App Usage is the easiest to use but powerful app/device usage management app.
It provides the following key features:
App usage history: gather the usage time about apps that you used
Activity history: gather the time that you open apps
Android: Asks if you really want to use an app (e.g. YouTube) and/or if you really want to use your phone
Windows: Press Hotkeys to take (forced) breaks and/or enter an intention each time you use your computer and get reminded of it!.
Wisdom Tree is a tui concentration app. Inspired by the wisdom tree in Plants vs. Zombies which gives in-game tips when it grows, Wisdom Tree gives you real life tips when it grows. How can you grow the tree? by concentrating!