If we have content sharing system which content is a kind of binary data and we want to apply a rewarding system using SMT, can we customize the posting content?
For example, a user can post an article which can be read and posted by only our app.
nope. If you want to use the Steem blockchain rewards mechanism, you have to be part of the consensus, hence to publish on the blockchain.
For example, a user can post an article which can be read and posted by only our app.
There is a very specific use case in which this would be possible, but I'm still studying it, so I'd rather refrain from giving a definite answer to this question.