edX

Founded by Harvard University and MIT in 2012, edX is one of the best websites to learn mobile app development. edX is an online learning destination and MOOC provider, offering high-quality app development courses for beginners for free from the world’s best universities and institutions to learners everywhere.

EdX currently has 1.2 million users and 29 universities participating or planning to participate in offering edX courses. App development courses online for free on this website have more than 130 global partners. With Open edX, educators and technologists can build learning tools and contribute new features to the platform, creating innovative solutions to benefit students everywhere.

Edx uses online learning software that uses interactive experiences. In addition to a sidebar that contains accompanying text and which students can "scroll" the text to see it in its entirety, the course also includes instructional videos with content similar to those of other sessions. School group discussions, online textbooks, and online forums for students to discuss, comment, and ask questions. EdX offers free certificates to those who complete the course but does not offer accompanying credits. Whether or not credit is provided for an online course is entirely up to the school offering the course

Website: https://www.edx.org/