GroupBy a list of associations with their keys

Question

How can I go from

as =  {
    <|A->{1,11},B->{1,12},C->{1,13}|>,
    <|A->{2,21},B->{2,22},C->{2,23}|>,
    <|A->{3,31},B->{3,32},C->{3,33}|>
}

to

<|
     "A" -> {{1, 11}, {2, 21}, {3, 31}}, 
     "B" -> {{1, 12}, {2, 22}, {3, 32}}, 
     "C" -> {{1, 13}, {2, 23}, {3, 33}}
|>

I think I should use some variation of GroupBy[as,condition] but I can't really figure out what condition should be.

Answer 1

This operation is performed by Merge:

Merge[as, Identity]

<|A -> {{1, 11}, {2, 21}, {3, 31}},
  B -> {{1, 12}, {2, 22}, {3, 32}}, 
  C -> {{1, 13}, {2, 23}, {3, 33}}|>

Answer 2

Another approach:

AssociationThread[Keys[as][[1]], Transpose@Values[as]]

<|A -> {{1, 11}, {2, 21}, {3, 31}},
  B -> {{1, 12}, {2, 22}, {3, 32}}, 
  C -> {{1, 13}, {2, 23}, {3, 33}}|>

Answer 3

GroupBy[Catenate @ Normal @ as, First -> Last]