You've described an existing approach actually, and unfortunately there is a big caveat. Duolingo and many other applications use gated or timed content windows in order to increase retention and form stronger long term habits.
The TL;DR of that loop, is that in order to achieve your goals within the app you'll have to come back later to do so, which sets up a daily usage habit.
The Sims mobile for example, you can't just keep playing the game, you have to constantly check back in to see how your timed tasks are going. For DuoLingo, you run out of hearts as you get questions wrong, so you have to keep checking back to see if your hearts have replenished in order to finish the lesson you were on.
It might genuinely be healthier, I think that would need to be studied, but it's not out of the kindest of their hearts that they do it, it's just another way to keep you on the app, albeit over a longer period of time.
The TL;DR of that loop, is that in order to achieve your goals within the app you'll have to come back later to do so, which sets up a daily usage habit.
The Sims mobile for example, you can't just keep playing the game, you have to constantly check back in to see how your timed tasks are going. For DuoLingo, you run out of hearts as you get questions wrong, so you have to keep checking back to see if your hearts have replenished in order to finish the lesson you were on.
It might genuinely be healthier, I think that would need to be studied, but it's not out of the kindest of their hearts that they do it, it's just another way to keep you on the app, albeit over a longer period of time.