Four minutes a day beats an hour on Sunday.

PrepQuest is a swipe-based flashcard app for tech interview prep. Revise JavaScript, React and system design interview questions in short sessions you can finish on a commute. One statement per card: swipe right if it's true, left if it's false, up if you genuinely don't know.

WHY IT'S DIFFERENT

• Guessing scores zero. With two choices, random swiping would normally score 50%. Here a wrong swipe cancels out a right one, so a pure guesser lands at exactly zero. The score means something.

• Levels open on accuracy, not points. You clear a level at 80% accuracy over your last 20 cards, so grinding an easy deck can't fake progress.

• Wrong cards come back. Anything you miss or skip returns tomorrow, then in three days, then in a week. Spaced repetition that targets exactly what you forgot.

• Say "not sure" without penalty. Swiping up costs nothing and tells the app which concept to bring back first.

SEE WHAT YOU ACTUALLY DON'T KNOW

Your results are broken down by concept, not collapsed into one number. You'll find out that your closures are solid and your event loop is not, which is the difference between revising and just feeling busy.

EVERY CARD EXPLAINED

After each swipe you get the reasoning, not just a verdict. The explanation is where the learning happens.

WHAT YOU CAN REVISE

JavaScript, React and system design, built for frontend and full-stack developer interviews.

BUILT FOR REAL CONDITIONS

Sessions load up front and run offline, so patchy mobile data on a train doesn't cost you your progress. Dark by default, one-handed, and designed for the ten minutes you actually have.

Free to use. No ads.