Timeline Dojo is a free game where you slot event cards into their correct place on a timeline. Rather than rote-memorizing dates, you train the sense of 'which came first' — the skill ordering questions actually test.
Questions are in Japanese (interface in English) and mix Japanese and world history, following Japan's Rekishi-Sōgō curriculum. One quick play at a time, the flow of eras sinks in.
Answer the same question correctly twice and it graduates into a mastery card; the ranking counts how many cards you have collected. You can drill only the questions you got wrong, and every day you play adds a study stamp. No sign-up is required and your records stay on your own device. (The questions themselves are in Japanese.)