Crear una aplicación para Android

m looking to create an application for android. [login to view URL] ( Argentina ) . In this product sold ( new and used) products of all kinds , in which you prune FILTER , putting price, area , whether it is new or used , if they published today , if it ends today the time of the publication .. Etc, etc. The idea is to generate the application filter option "starts today" and notify me when they publish a warning CERTAIN SPECIFIC PRODUCTS in real time. or every few minutes ( not so) example, if a person 5 min publicaca an Iphone on page 5, which arrives automatically alert me just released an iPhone 5 price and the place where the person is located , with the name and price . and if you can place (where it is ) eg ( Buenos Aires , Chaco, Santa Fe ) on the publicaicones . The idea is this , this page of " MercadoLibre " in Argentina , sell products people like you and me , used or new . I buy products at great prices with a filter that says " Starting Today " which means that a public person TODAY product , eg iphone 6 , Sometimes there are people who post at a very affordable price , the issue is that I have to be in pc , updated every 5 minutes , maybe now that any person publishes an iphone 6 , but in 1 minute anyone who published a iphone 6 at a low price , but as I do not actualize and not checked, and another saw him first and as it was low I buy it , I buy it and lost , and so with all products , I am buying and selling of products. the idea of ​​the app is to tell when you post something new to warn me , so I see if I serve or not to buy it , so I q no longer be on the pc updating and revising . see pictures please put real price and real time