The OB Wheels app will make the most of your smartphone's screen and camera. You can view a sonogram or a picture of your baby and see when the baby will be due. You can also view your own pictures, and it will be able to calculate the due date based on when you took the picture. The app has a calendar for the month so that you can check the due date for your baby. It will work for both sonogram reports and LMP. It can also calculate the due date for the next month.