Use the “Ask Seller a Question” button on each listing to message the seller with any questions or comments that you might have on their app. This is a good way to communicate with sellers/developers before you put an offer on the table. You may use this feature before, during, and after your negotiations.
Please note, we heavily discourage trying to exchange personal contact information. We realize that some buyers and sellers prefer to deal over Skype or personal email, but just know that we can't use any conversation had offline as evidence should there be a dispute. Also, we aggressively protect against deals being taken off of our site.