Question: Is there a learning app that offers a comprehensive set of study materials, including textbooks and mock exams, and works across multiple devices and languages?

For a more general-purpose learning app that includes study materials like textbooks and practice exams, and that works on multiple devices and languages, Vaia is a strong contender. This AI-powered learning app offers a variety of tools like smart to-do lists, study sets, flashcards, notes, study modes and AI tools. Vaia's AI can explain any subject, and it uses scientifically-backed learning techniques like Spaced Repetition, with 94% of users reporting better grades. It's available in English, Spanish, German, French and Italian and is geared for students of all ages and skill levels.

Another strong contender is Quizlet, which has more than 300 million users and offers a range of tools like Magic Notes, Q-Chat, Expert Solutions, Learn and Test Modes and Spaced Repetition. Quizlet applies learning science methods to its tools, so it should work well regardless of your learning style. It offers millions of vetted explanations and supports a range of question types, including multiple-choice and written-answer questions. Quizlet offers free study sets and modes, but you can upgrade to Quizlet Plus for more features.

If you need help with homework 24/7 and textbook answers, Chegg is a good option. Chegg offers step-by-step textbook answers, expert Q&A, math help and special tools for writing and exam prep. The company says its tools are designed to help students succeed from start to finish, with 91% of customers saying they've done better in school and 92% saying they have a better grasp of the subject matter. Chegg also offers tools for teachers, so it's a good option for schools and universities.

StudyX is another general-purpose tool that offers homework help, deep learning with AI models and paper research help. It's got a clean interface and works as browser extensions for tools like Google Docs, Gmail, Zoom and more. StudyX is designed to replace other tools, so it's a good one-stop-shop for students from any university.