application similar to Instagram and classified

I am looking for developer to build applications on mobile phones compatible with the IOS(IPhone) and android .The application similar to Instagram and classified ,that is ability to post goods (transfer photos and other details of that goods to the server), just similar but not the same as Instagram App. Details and the ability of the application Capability Login via Facebook, GPS, share, comment, and camera. Principles 1. When the sellers want to sell the products. The details of products such as photos, kind of products, type of products, brand and GPS. will be transferred to the server as a post. When the application user read or comment on the post the system will alarm to the seller to know immediately. 2. When the customers want to buy products, the customer will post their own demand which compound of varied keywords for example kind of product and brand on the application page, then all the details of demand will be sent to the server. The system (a software program) will search keyword in database which contains of supplies from the sellers in order to match keywords in the database if matched the system will alarm to the application page of the seller this process will repeat itself whenever there’s new post on application page until the customers delete their post. After you understand the principle of this application and agree on proposed fee rate. I will inform you more details and the design of the application.