title: AngularJS vs 2 vs 4 and Ionic 2vs3
body: <p>Is there a benefit to converting/learning Angular 2 over Angular 4 when moving away from
  AngularJS?</p>
  
  <p>Is there a reason to not jump directly to Ionic 3 and Angular 4 from Ionic(1) and AngularJS(1)?</p>