I checked all the answers to my question (how to add two mobile numbers to one contact in iPhone) but I didn't see a clear answer.
A lot of my contacts have more than one mobile number, and while my android phone syncs beautifully with gmail contacts (multiple mobile numbers), my iPhone 4 only allowing me one mobile number. After that when I click on add, I get a list of home,work,fax,etc. But no second mobile number.
My 5 years old Nokia phone let me add custom labels to any phone number, like I can add a number and name it "boat phone" , gmail contacts also can do it.
Any help is greatly appreciated.