Wit.ai

Wit.ai (famously acquired by the massive tech titan Meta/Facebook) is a wildly explosive, fiercely agile, and completely free NLU platform. While enterprise giants charge thousands of dollars for API access, Meta built a massive global empire by giving developers world-class, mathematically terrifying Natural Language Understanding for absolutely zero cost. The absolute core differentiator of Wit.ai is its "Frictionless Developer Experience and Crowdsourced Intelligence." A solo developer building a smart home app can mathematically train a Wit.ai model in 5 minutes to understand the intent 'Turn on the living room lights'. Furthermore, Wit.ai learns globally; if a developer in Japan trains the AI on a new phrase, the underlying engine mathematically improves for everyone. Because it completely democratized access to high-end NLU, offering staggering ease-of-use, perfect integration with Facebook Messenger, and a 100% free pricing model, it is heavily favored by independent developers, IoT hardware startups, and rapid-prototyping teams.