Wolfram Alpha is an online service that answers factual queries directly by computing the answer from externally sourced "curated data", rather than providing a list of documents or web pages that might contain the answer as a search engine might.
Photomath is a mobile application described as a "camera calculator", which utilizes a phone's camera to recognize mathematical equations and to display the step-by-step solution onscreen.
Khan Academy is a non-profit educational organization created in 2008 by Salman Khan with the goal of creating a set of online tools that help educate students. The organization produces short lessons in the form of videos. Its website also includes supplementary practice exercises and materials for educators.