Hey.
History or reputation on steem is just a tool to evaluate the trust but absolutely not a proof of the app privacy or security. To be sure of that point, the best is to check the code base, the application is automatically pushed from the code base so nothing between the code showed and the code served is modified. You can trust me, the app will not share any data with a third-party without notifying users. This saying is also not an absolute proof, the best is check the code personally or have some review from different community members.
I hope that was the clearest possible, we're here to answers more questions :)