Best way to Read WordPress as JSON

I attend to create an android version of my WordPress blog. So, i do some google search and Stackoverflow search to find the best way to do this works:

1. find the count of the post
2. category's names.
3. reed posts, page by page (or a number like read 10 post for every request)
4. reed posts by they tag and act like 3.
5. get the thumbnail for images.
6. find the number of comment for each post.
7. reed all comments.
8. send comment.
9. and ...

So in my research s i found some plugins and because of the company who make that, i think WP REST API is more trustful than the others but there is other plugin like JSON API. so based on my needs, what is the best choice?

PS: I find out the WP REST API have a version 2, but they say, it is not good enough to being used in large app. Thanks.

via Chebli Mohamed