Best ways to study in 5 minute bursts?

Hey guys! I'm super into finding new ways to memorize Japanese right now. I've been trying to use every spare minute I have but I'm getting a bit bored of just flipping flashcards on my phone. Does anyone have quick tactics for when you only have like five or ten minutes? I want to make sure I'm actually making progress even when I'm busy. maybe some listening ideas or quick writing drills?