ePen vs Rainy AI

ePen provides calligraphic writing, ink painting and various painting functions, which contains brush sizes, stroke pressures, borders and background color options. Even more, ePen gives you the option to create personal stamps. In addition, the app accommodates knowledge of Chinese characters that allow you to have the insights into the evolution of Chinese characters, provide handwriting samples and scholar work gallery to learn well-known calligraphy, and also enable you to store all your work.

Rainy is your immersive AI tutor — not just for solving problems, but for chatting, practicing, and growing with you every day. AI COMPANION CHAT Choose a gentle or feisty personality and chat with Rainy anytime — ask questions, get encouragement, and just talk about your day. PHOTO HOMEWORK HELP Stuck on a problem? Snap a photo and get an instant, step-by-step explanation. Still confused? Just ask a follow-up question and Rainy will walk you through it. SPEAKING PRACTICE Practice real conversations — ordering at a restaurant, shopping, asking for directions, introducing yourself. Rainy speaks, then it's your turn automatically. Get instant pronunciation feedback and track your progress over time. DAILY QUESTS Review vocabulary, practice one conversation, solve a few problems — complete your daily quest to build a study streak and a real learning habit. STATS & SHARING See your study time, problems solved, and vocabulary learned at a glance, and turn your progress into a shareable card. Supports learning in Chinese, English, Japanese, and Korean — whether you're prepping for an exam, building conversation skills, or just trying to study a little every day, Rainy is right there with you.