Justin Guitar is one of the best free resources for guitar learning available. One of the lessons I appreciated most was Justin Guitar’s lesson on the A chord. I started learning the A chord with Fender Play and the traditional 1, 2, 3 fretting for the A chord. Justin teaches a 2, 1, 3 fretting. Both the 1, 2, 3 and the 2, 1, 3 fretting will both allow you to play the A chord.
The benefit of the Justin Guitar method is that transitions to the D chord and the E chord is much easier. Justin talks about it in his video on anchor fingers. It might not mean as much for better, more experienced players, but to me as a total newbie it made and still makes chord transitions easier.