Memrise is an education and reference application that helps users learn new languages, vocabulary, and facts. The app provides a variety of tools and activities that make it easy to learn and remember new words and phrases, as well as test one's knowledge. Additionally, Memrise allows users to create their own courses based on their interests and goals. The app also includes audio and visual content to ensure users gain the most out of their study sessions. The app is available for free on both iOS and Android devices.
Highly customizable and open source.