Enchiridion vs CS++ AP CSP

Learn anything. Remember it for life. Enchiridion turns big subjects into short daily sessions that stick. Answer a few cards, read the reasoning behind every answer, and let spaced repetition decide when you see each idea again — right before you'd forget it. WHAT'S INSIDE • 9 learning paths: Become an Adult (taxes, insurance, contracts), Taxes & Money, Health & Wellness, Psychology & Mind, Philosophy, Science & Nature, World History, Tech & AI, Art & Culture • 3,000+ original quiz cards, each with a plain-English explanation and feedback that names the exact misconception behind a wrong answer • 324 deep-dive articles (typically 4,000–6,500 words) with named sources and further reading — the "why" behind the facts • Verified content: 1,500+ cards fact-checked against primary sources (IRS, SSA, NIST, peer-reviewed literature); tax and money figures use the 2026 IRS numbers HOW IT WORKS • Scheduling runs on the open FSRS-5 spaced-repetition algorithm with per-card adaptive difficulty, so review intervals truly expand as you learn • Story moments: short, skippable dialogue from characters tied to each path appears halfway through a session — turn it off anytime in Settings • Golden cards, speed bonuses, combo cheers, streaks, daily quests, and level-ups keep sessions warm without getting in the way • Deep dives render real tables — truth tables, tax brackets, fund comparisons • iCloud sync keeps progress across your devices WHO IT'S FOR • Lifelong learners who want durable knowledge, not trivia • Adults catching up on the practical things nobody taught them • Students and professionals who need retention, not cramming The name comes from the Greek word for handbook: a practical guide you carry with you. SUBSCRIPTION NOTICE • Enchiridion offers auto-renewing subscriptions for full access to all paths, deep dives, study sessions, sync, and progress tools • 7-day free trial available for eligible new subscribers • Payment is charged to your Apple ID at confirmation of purchase • Subscriptions renew automatically unless canceled at least 24 hours before the end of the free trial or current period • Manage or cancel anytime in your App Store account settings • Privacy Policy: https://enchiridion.io/privacy • Terms of Use (Apple Standard EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ • Public service terms: https://enchiridion.io/terms

CS++ AP CSP is the complete AP Computer Science Principles course in your pocket — fully offline. WHAT YOU GET • 11 units covering every topic in the College Board AP CSP Course and Exam Description (CED) • Hundreds of inline multiple-choice "Check Your Understanding" questions, with hints and explanations • Lesson text written for high school students — clear, conversational, no jargon walls • Worked examples, common-error callouts, and AP-prep notes throughout • Progress saved on-device, persistent across sessions • Unit 1 (The Computer) is free; full course unlocks for $9.99 (one-time) THE 11 UNITS 1. The Computer 2. Data Representation 3. Compression & Encryption 4. Data Analysis & Visualization 5. Algorithms 6. Programming Languages & Abstraction 7. The Internet & HTML 8. JavaScript Basics 9. Procedures & Lists 10. Create Performance Task Prep 11. Impact of Computing & Exam Strategies WHY OFFLINE All lesson content is shipped inside the app — no streaming, no fetching. Use it on a plane, a Chromebook with restricted Wi-Fi, or anywhere with no signal. WHY CS++ We've taught AP CSP online at csplusplus.com to teachers and students across the United States. This app distills the full course into a focused study tool — same content, same alignment to the 2025-26 College Board CED, packaged for the device you carry every day. VIDEOS NOT INCLUDED The course videos that accompany each lesson on csplusplus.com are not bundled in the app (to keep the download small and fully offline). Each lesson includes a "Watch on csplusplus.com" link that opens the corresponding video in a browser. PRIVACY No account creation. No sign-in. No analytics or tracking. All progress lives in app storage on your device. No data is sent to our servers. THE PURCHASE The free tier covers Unit 1 — enough to evaluate the lesson format and inline checks. The full unlock is a one-time $9.99 purchase that unlocks all 11 units forever, with no subscription. AP, Advanced Placement, and AP Computer Science Principles are registered trademarks of the College Board, which is not affiliated with and does not endorse this app. Built by Yellow Dart Publishing.