The iPhone keyboard has support for typing characters like ¿ by selecting a similar character on the keyboard and holding the key for a short time. However, there doesn't seem to be a way to type a ~ character (a tilde). How does one do that?
On keyboard, press the "123" button to bring up numbers. From here press "#+=" to bring up more characters. ~ is the 4th from the left, second row.
Answered on an iPhone :D