Encyclopedia of Outer Space vs Tavi

Explore the universe, from stars and galaxies to space exploration. Read 434 articles, search for a topic, and save discoveries to revisit. START WITH FIVE FREE ARTICLES New readers can choose any five different articles. Your chosen articles stay unlocked, and revisiting them never uses another choice. Existing readers keep previously granted access. MAKE DISCOVERIES YOUR OWN • Search article titles and full text • Follow links between related topics • Save articles and return to your reading position • Continue recent reading and track your progress • Explore connections through the timeline and graph • Find article sources and image credits inside the app CHOOSE YOUR ACCESS Own the full encyclopedia with a one-time purchase for complete offline reading. Or choose monthly or annual Premium for the full encyclopedia plus AI chat grounded in this subject's articles. Eligible new Premium subscribers receive a three-day introductory trial. Subscriptions renew automatically unless canceled through your App Store account. Current local prices and terms appear before purchase. Restore Purchases recovers eligible previous purchases. Earlier full-version ownership includes encyclopedia and offline access; Premium AI requires a subscription. Internet access is required for AI chat and purchases. AI answers may contain errors; consult the linked sources. Article text is derived from Wikipedia. Images come from appropriately licensed Wikimedia Commons and other open sources. Source links, licenses and credits are available in the app. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Learn any language through real conversations with AI — not flashcards, not multiple choice. Just you and a personal tutor that adapts to your level. Tavi connects directly to ChatGPT, Claude, or Gemini to create personalized lessons in real time. Instead of paying $14/month for a language app, you pay the AI provider directly — pennies per lesson. Heavy daily use is still under $1/month. HOW IT WORKS We'll walk you through connecting your ChatGPT, Claude, or Gemini account. It only takes a minute — and Google Gemini is completely free to start. Your credentials stay securely on your device and are never sent to Tavi. LEARN YOUR WAY - Daily Lessons with rotating themes tailored to your level - Photo Lessons — snap a menu, sign, or document for instant vocabulary - News Lessons — practice with today's headlines - Custom Lessons — paste any text and learn from it - Placement Test — take a quick AI conversation to find your level 10 LANGUAGES Spanish, French, German, Japanese, Korean, Mandarin Chinese, Portuguese, Italian, Arabic, and Hindi. Beginner to Advanced (CEFR A1-C1). STAY MOTIVATED - Daily study streaks with milestone celebrations - XP rewards for lessons and consistency - Progress dashboard with weekly charts and statistics FREE TO START 1 free lesson every day. All languages and lesson types included. Upgrade to Pro for unlimited lessons, streak freeze, and the full analytics dashboard.