Android/iPhone GPS application taxi booking

We require basic application for the sms booking of taxi cabs. App needs to be very simple for usage scenario below User selects app App loads Single screen app interface with title at top app interface utilises form layout First input screen is has 2 buttons. first for "Now" and second for "at time" - if "at time" is selected then time/calendar box opens for user to define date and time. Once complete, user moves to second input screen. Second Screen has 2 buttons. First is "My location" and second button is "edit address" - If "My location is selected, GPS is used on phone to track location. If "edit address" is selected then user can input their address manually. Recently used addresses should have last 5 location history. Final Screen has "Place request" or "Cancel" buttons. -If "place request" is selected, the booking time (first input screen) along with the address or GPS location is sent to a mobile phone number to be handled by company representative -If "cancel" is selected, order is cancelled and app returns to the first input screen. This my first project and welcome feedback for this project. Please send through details of previous application development experience, estimated costs and time needed to complete. Regards.