MOKOSOFT games are one of my favorite Japanese resources of the year. I have many of them installed on my iPhone (free, and available in US App Store). I’ve mostly been trying the crossword puzzles, with varying results. They seem to require N3ish vocabulary and some Japanese pop-culture and specific knowledge about the prefectures. Still, I can get a bit here and there, and it’s helpful just parsing the clues. They also have a word game called もじたん which is easier (at least to start) but escalates quickly.
Still poking around with some of the others, but thought I’d share in the meantime.