Language Learning vs Relativity Simulator

Polyglot helps you learn several languages at the same time, all on your device and all private. Most apps make you pick one language and follow one rigid path. Polyglot is built for people who want more. Study Spanish, French, German, Japanese, Korean and more side by side, with tools that adapt to you. WHY POLYGLOT - Learn many languages at once, with a color for each one so they never blur together. - A private, on-device AI tutor builds lessons, quizzes and conversations for any topic you pick. - Smart flashcards use proven spaced repetition so you review at the perfect moment. - Fast, friendly games turn daily practice into a habit. - Speak out loud and get instant pronunciation feedback. - Translate anywhere, even offline. - Your data stays on your device. No account required. SMART FLASHCARDS Polyglot schedules every card with a modern spaced repetition engine, so you spend time on the words you are about to forget and breeze past the ones you know. Each card includes an example sentence and pronunciation, with text to speech in a single tap. AN AI TUTOR IN YOUR POCKET Type any topic, like ordering food or a job interview, and Polyglot writes a focused lesson with vocabulary, useful phrases, a short overview and a tip. Add the new words to your flashcards in one tap. Practice freely in conversation mode and get gentle, in context corrections, or take a fresh AI quiz made just for you. It runs on device, so it works without a connection and keeps your practice private. GAMES THAT MAKE IT STICK - Match Pairs: link words with their meanings. - Fill the Blank: complete the missing word. - Build the Sentence: arrange word tiles into real sentences. - Listen and Choose: train your ear. - Say It: speak the answer and get scored. Mix all of your languages in one session to get sharp at telling them apart. SEE YOUR PROGRESS Track reviews, sessions and streaks. A clean chart and calendar show your activity at a glance, and a mastery bar for each language shows how far you have come. TRANSLATE ANYWHERE Quick translation is built in and works offline. Prefer the highest quality? Download an optional model for full offline translation anywhere you go. PRIVATE BY DESIGN Polyglot works without an account and keeps your learning on your device. Optional iCloud sync keeps your cards in step across your iPhone and iPad. LANGUAGES Learn Spanish, French, German, Italian, Portuguese, Japanese, Chinese and Korean, explained in the language you already know. Start today. Pick your languages, set a daily goal, and build your streak.

Relativity Simulator is an interactive relativity toolkit built strictly on the axiomatic foundations of modern physics. There is no "hard sci-fi" here — every result traces back to the Lorentz transformation of special relativity or the Einstein field equations of general relativity, and is verified against numerical truth fixtures. 【Real physics, not imagination】 · 20 interactive modules covering core effects from special relativity to black holes, gravitational waves, and curved spacetime; · Each module ships with precise charts, adjustable parameters, and a "Theory Card" with a fully visible derivation chain; · All demo numbers are recomputed locally on your device from real CODATA constants — nothing is fabricated. 【Phenomena you can verify yourself】 · Gravitational time dilation: why clocks run faster up high — ~80 ns/day faster atop Everest, ~38 µs/day faster on GPS satellites; · Twin paradox: fly to 4.22 light-years at 0.8c and the Earth twin ages 10.5 years while the traveler ages only 6.3; · Tidal disruption: why you get stretched into "spaghetti" falling into a black hole — small holes tear you outside the horizon, supermassive ones only after you cross it; · Plus light bending, gravitational lensing, the Schwarzschild horizon, frame dragging, and mass–energy equivalence E=mc². 【Built for learning and teaching】 · Volume-based progression: kinematics → gravitational field → black holes → cosmology → applications; · Bilingual (zh/en) system notes ship with every effect: derivation, physical quantities, and references; · Chinese / English UI follows your system language. 【Privacy first】 The app collects, stores, and transmits no personal data, embeds no third-party SDKs, and runs every computation locally on your device. Whether you are studying, teaching, or simply curious, Relativity Simulator lets you actually run the "invisible spacetime" and watch it.