Hi,
We do not have iphone so we won't be able to test it and understand the problem.
Do you have more details about the problem ?
Is it during the checkout, for a specification action which is not working ?
If your store is working fine for desktop and not for iphone, my first idea is to check the javascript errors.
Regards,
Jerome - Obsidev.com
HikaMarket & HikaSerial developer / HikaShop core dev team.
Also helping the HikaShop support team when having some time or couldn't sleep.
By the way, do not send me private message, use the "contact us" form instead.