iPhone Ordering

iPhone application required to place orders. The user will be presented with a list of groups. On selecting a group, a list of items will be shown. They can then select an item to order. The groups and items are to be shown as pictures with prices against items (scrollable lists). Would prefer all data to be held locally with a defined update process (to the server). Volumes: expect to hold up to 300 products across c15 groups. When all items have been selected, user will complete the order by a button click which will create an order on the server (hosted) using either web services or simply file creation (tbc). If the device does not have 3g/wireless connection at the time, the order will be held and user can retry. Therefore need confirmation back from the server when the order has been placed. Additional options include the ability to review list of items selected so far and increase quantities or remove items. User must log in - order will be flagged against the logged in user. Before placing an order, user must enter an order id (free text). User can enter an email address at any point before completing the order. That's the lot!