Very possible. All you need is a library to handle https (I believe it may have that standard) and then you just need to send specific predefined requests to any of the nodes and they will return with answers. Most of the steem-python library actually works by turning the JSON into dictionaries to make it easier to handle on the users end. In order to do any operation on the blockchain you would first need to have something made to write JSON.

Basically the steem blockchain is a list of JSON (as shown in part 3 I think) and as long as you can handle sending and receiving JSON over https then it is possible.

Like the blockchain itself is written in C++ but there are official API libraries for python and javascript and unofficial libraries for ruby and possibly other languages.