The App must be made for android and ios. It is a marketing service. There will be 3 types of users: the seller, the public and the administrator.
The seller must have informations like adress,rating, photos, followers, API to google maps or Maps(IOS) and other info that will be discussed later. The seller can put ads by that after being submitted they should notify people through push notifications if they were interested in the seller's profile in the first place. A good push notification system is needed.
The other users(the public) need to have a Name, Email or mobile phone number, Age and Gender associated to them in order to create an account. They can sign up through google+ or facebook.
The service needs to have a secure way for the seller to execute the transactions to pay for the subscription of our service. Sellers can pay through Visa, MasterCard and PayPal.
The administrator should have the access to the database that contains all users registed in the app.
The administrator should also have the function to approve or eliminate ads submitted by the seller as well as to eliminate users.