Which case does it take?
A new game for the prepositions. First you sort them: mit, für, wegen, in… each goes to the case it takes, the accusative, the dative or the genitive, and the two-way ones to Both. Then you use them with the nouns from your own stories: „mit ___ Kollegin“, „Ich bin in ___ Küche“. Tap the article that goes in. With a two-way preposition the verb gives it away: going somewhere takes the accusative, being there the dative. A miss is put right where it stands, with why.
Where: In Games, from home. Free, and it keeps your streak.