Outlier is a free, unlimited rare-answer trivia game in the Krillion style. You get a category such as name a river, a cheese or an NBA team, and one answer. Obvious picks score a little, rare correct picks score a lot, and your grade decides how far your cat pilot UFO flies. No daily cap, no download. Independent game, not affiliated with or endorsed by Krillion.
I loved rare-answer trivia but hated that the daily version ends after one round, so I built an unlimited mode that lets you keep playing as long as you like.