In your open <select> tag you have MULTIPLE capitialized. Try putting it in all lower case letters. It COULD be that whatever version of the iPhone and iPad the users have are having a hard time rendering multiple in all capital letters. It's worth a try.
Another thing to try is in your open <select> tag the name="to". You can try taking out the brackets and see if that has any effect.
A third thing to try is you have most property values in single quotes. Try putting them all in double quotes.
My initial guess is that any of the three above could be giving the iPhone and iPad rendering engines a hard time. It's worth a try.