4+
while we take care of your subscription management.
Mobile
SDK by Qonversion.
vs. average for the Games category, $, by region
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This app is a great example of do one thing, and do it well. You get 3-5 shogi tsume (mating) problems a day, a good mix, usually more towards the beginner/intermediate level. This app won't teach you the rules of shogi, and how to identify pieces, but any English speaker who's dabbled in shogi should expect that. The hints are also in Japanese, but English speaking shogi players should expect that as well. If I were to recommend something, it would be for a paid version that could remove the ads. Though, compared to most free apps, the ads are not annoying at all.
Daily tume-shogi(mate) and tesuji problems (provided by Mynavi corporation).