I used to play a lot of Neko Atsume, and had collected everything that could be collected. Unfortunately, since I chose to finally change my gmail account (to a less unprofessional one) when switching phones, I lost all of my progress 
I decided to replay the game, but this time in Japanese, and have found it to be a very good but also surprisingly decent source for language immersion.
Especially the shop with their visual and lingual description of their items are great, but the cats also each have their own name (which is often a pun), personality, and favorite toys.
An unexpected teaching tool however, is the daily password that you can enter for a few bonus fish (the currency of the game), with a sizeable reward for each set of 5 passwords you entered. These words are 50/50 kana loanwords/kanji-based words that I have never seen before, which you then have to write down somewhere else. This is especially great for reinforcing kanji readings. The words are usually referring to little items around the house, nature, or specific holidays and seasons.
Just thought I would share since it’s very low maintenance and a passive background game, it doesn’t need any microtransactions (just be patient), and as a fun bonus, it also teaches a little bit of Japanese every day 
EDIT: As an exercise, I think I’m going to make this a thread where anyone who wants to join can discuss the daily password, and discuss any details around it if it’s interesting
EDIT 2: I’m continuing logging the password in a more central thread here Neko Atsume Password Database
Thank you for sharing, I didn’t know this game 