Hi Michał Kędrzyński, Hope you doing Well.
Thanks for your feedback. And ofcourse, AngularJS is no more a future trend now. But it is true that Google’s Angular team released Angular 2 as a complete makeover of its original Angular 1 framework.
In fact, Angular 4 is an improvement on Angular 2, but a total rewrite of AngularJS. So, I will update my blog with “Angular4” very soon.