Write an iPhone application

Need to develop a bulletin board like mobile app. but with little more features in it. If you can do the following options in both iphone & android then contact me. most importantly need good interface . graphic design highly matters here . as UI design screens are ready i want everything to be perfect as it is UI design screen. This app has many icons, each has its own function 1) like Buy sell- one can post ads other the see posted ads for buying like OLX 2) developer should know using GPS system in app. ldesign needed ike slide bar should be der, just by sliding front or back radius of search in map should be increased or decreased. others are simple once . if you know these 2 contact me if you can do in min buget. if i like ur output i can commit for 2 more project of my friends i assure you . I have my UI design screens ready .just to see those screen and then just start coding. All d best.