Most apps that help you learn languages have features where you select options or swipe away wrong answer cards — you’re more or less interacting with a machine. Language-learning app Praktika is adopting a different approach: It lets you create personalized AI-powered avatars to replicate the experience of having a private tutor, leveraging inflections like tone of voice and emotions to help make learning a language feel more natural. Praktika claims to have 1.2 million active monthly users acr...