My client hired me to build an iPhone app. The contract states that the app has to work on all iPhones that can run iOS8 or higher. He just sent me an email asking why he cannot install it on his iPad. I think he didn't really understand that iPhone doesn't include iPad, when he signed the contract.
How do I tell him politely, that he will have to pay more for adding iPad support to the app?
It may be important to know that he hasn't paid the full amount yet.