Kotoba is described as 'Hands-free, voice-activated Japanese vocabulary trainer using spaced repetition, speech recognition grading, native example sentences, and offline browser access' and is a language learning tool in the education & reference category. There are more than 25 alternatives to Kotoba, not only websites but also apps for a variety of platforms, including iPhone, iPad, Android and Android Tablet apps. The best Kotoba alternative is Duolingo, which is free. Other great sites and apps similar to Kotoba are Memrise, Rosetta Stone, Lenguia and Language Transfer.