Ionic 3 was the newer version of Ionic, an open source SDK that enabled developers to build mobile apps using standard web technologies (HTML, CSS, and JavaScript). Ionic 3 finally took a back-seat to Ionic 4 in 2019 after 2 years. Ionic 3 was paired with Angular 4 and above.
GitHub Repository: https://github.com/ionic-team/ionic
Documentation: https://ionicframework.com/docs/v3/
