Sotto vs SpeakPal

Sotto is open-source, self-hosted language-learning software for structured CEFR courses and private practice. Its course covers grammar, reading, listening, speaking, and writing, with advancement tied to demonstrated mastery; separate practice is not gated by course progression. A vocabulary and grammar memory graph uses SM-2 spaced repetition to schedule reviews and help shape adaptive listening. Learners can build classes from articles, papers, YouTube links, or topics, with material leveled to a CEFR course and citations provided. Configurable AI and speech services include OpenAI, Anthropic, Ollama, faster-whisper, and Kokoro; Gemini Live supports spoken translation. The application, database, and files run on the operator’s own stack, and the maker documents an offline setup using the learner’s hardware. Access options include a browser-installable PWA, a desktop launcher for macOS, Windows, and Linux, a terminal client, and workbook PDFs for iPad annotation. Sotto is free to run under AGPL-3.0, but users pay configured AI and speech providers directly. Content sent to cloud providers is subject to those providers’ terms.

SpeakPal is an AI language tutor for conversation practice in English and 30+ languages, with feedback during practice. Guided role-play covers situations such as work, travel and daily life. The tutor corrects grammar in real time, while a pronunciation coach gives feedback on accent, rhythm and stress. Learners can download lessons, training materials, exercises and teacher audio MP3 files for offline practice. Teen Protection Mode provides safeguards and age-appropriate features for younger learners. SpeakPal is available on Android, iOS and the web. Its free plan offers daily conversation practice and basic learning features, but does not include unlimited use, course downloads or an AI language level certificate. Monthly membership costs $12.90 a month and adds unlimited use, pronunciation guidance, role-play, downloads, and text and voice conversations. Annual costs $79.90 a year and includes those features plus a certificate with QR verification and a shareable URL.