Most of the apps to learn Japanese/Chinese seems to focus on the reading part, where it will present a word, and ask the user if they remember the meaning/pronounciation.

I find that I learn much faster (and remember a word for longer) when I focus on writing, instead of just... look. And writing is something most apps just skip. Some apps do show the animation of the stroke orders, but I think the user needs to be proactively write it down somewhere to remember it better.