mobile application like foursquare

we want to build two mobile applications (iphone and android) for a foursquare like web application that we currently design. - users will create an account (facebook/twiter login should work) - add/invite friends from twitter facebook accounts - check-in to a place - merchants will create punch cards and/or %bonus on puchases from the web app. - see a list of places near by (geolocation) and for a criteria that give punch bonus and % amount bonus on purchases. - merchants will give the user printed qr code, customers will scan and the web side app. will calculate a bonus for the user. this can be a punch bonus or %bonus on the money spent there. - see on a seperate tab punch cards and how many punchs user has on each card and money bonus. - user will be able to redeem fullfilled punch cards and - see friends activity (a seperate tab) - rate and comment on the checkins - the mobile application will be able to scan qr code and communicate with our web app. (send/receive/show data) Submit your expertise on the above tasks, your best offer and achivable schedule. all codes will be delivered open source.