Angular is an open source project mainly run by Google and a dedicated community of developers. The group's announcement that it was changing the direction of the Angular framework in version 2 was met with some hostility. Since Angular was started as a web apps only framework, some developers were unhappy about the plan to make version 2 cater more for mobile apps.
The reason why the Angular group implemented the changes is because they wanted make it easier for developers with existing web app coding skills to move into mobile and desktop app development. According to Angular's website:
Learning Angular 2 gives you the tools you need to build apps for desktop, mobile web, Android, and iOS. Angular Universal provides for server-side rendering for fast initial views on mobile web. Ionic and NativeScript let you build hybrid and native UI mobile apps. Web worker support keeps your app UI fully responsive no matter how heavy the load.
Angular 2 also boasts faster rendering and page update times for apps compared to Angular one.
You can learn more about the features of Angular 2 and try out the framework on Angular's official page. If you've developed an app using Angular 1, there are also instructions on the website on how to migrate your app to Angular 2,.
[Via Angular JS Blog]