System Design Refresher vs Paper Fold

System Design Refresher is a free study companion for software engineers preparing for system design interviews. WHAT'S INSIDE • 30+ system design articles covering distributed systems, databases, caching, and more • Engineering blogs from top tech companies (Google, Meta, Stripe, Airbnb, and more) aggregated in one place • AI-powered flashcards with spaced repetition • Ask AI to summarize or explain any article in plain language • Favorites, reading progress tracking, and custom RSS feeds FEATURES • Works offline — articles download for reading without internet • Dark mode, font customization, and text size controls • Face ID / Touch ID lock for privacy • Sign in with Google or Apple, or use as a guest with no account required

Learn origami one clear fold at a time with Origami Craft. Explore a collection of paper models and follow simple illustrated instructions at your own pace. FEATURES • Step-by-step folding guides with clear crease lines and directions • 12 models across animals, nature, journeys, classics, shapes, and love • Beginner, intermediate, and advanced difficulty levels • Interactive folding game to practice matching target shapes • Search, favorites, personalized recommendations, and progress tracking • Available in English, Vietnamese, Spanish, and French From a classic paper plane and boat to a crane, butterfly, frog, heart, and more, Origami Craft makes it easy to start folding and keep learning. No account is required. Your favorites and progress stay on your device, so you can learn and play offline.