To uninstall iBird from iTunes go to the LIBRARY in the left hand navigation menu. Then select Apps under LIBRARY and you will see a list of all your Apps. Now right click on any app you would like to remove and select Delete from the drop down menu. Click remove and then click Move to Recycle Bin.
To reinstall iBird in iTunes you’ll need to sign into iTunes using the same Apple ID and password you used to originally purchase iBird. Since you’ve already purchased it and should have a receipt, you won’t have to pay for it again. After you click “Buy” and confirm the purchase by entering your password, you’ll be advised that you’ve already purchased this item. To download it again for free, select OK.
After you connect your device to your computer, click on your device under the section DEVICES. Once you do that, click on the tab that says “Apps.” You will want to make sure that the iBird app you have downloaded is checked so you can sync it.
Sync your device to your computer.