I tried to get my Google Contacts onto my iPad with almost disastrous results. I have an android phone using Google Contacts for a couple thousand clients as well as all my personal contacts. I have been very impressed with Google contacts in its flexibility to seamlessly organize, sync and update my contacts without losing important information or creating multiple contacts. It is easy to combine contacts if I get an e-mail from a client that isn't in my contact list. I need to continue using Google Contacts but would like to same information to sync to my iPad contacts.
I got the new iPad for a gift to use for client presentations. I tried to sync my Google contacts with the Apple contact app on my iPad. I eventually figured out the only way to do this was to use Microsoft Exchange which would covert my Google contacts to a Microsoft format and then would sync with Apple's contact format. In the process I noticed that many of my numbers and some addresses didn't sync to my iPad because in Google Contacts I had created custom fields for them.
Since Microsoft doesn't recognize custom fields and there is a limit to, for example, the number of phone numbers per contact in Microsoft Outlook Exchange, it made syncing my Google Contacts to the iPad useless. There is no way I could go through all my contacts to change them to standard field names and I wouldn't want to anyway since the custom fields gives me vital information on client numbers for different individuals and departments in each contact. Also, many of my contacts for organizations have more than a dozen numbers for different departments and using the Microsoft Exchange sync process allows less than a dozen.
Even worse, when I went to look at my Google contacts on my phone and computer, the Apple contacts on my iPad had changed my Google contacts custom name fields for phone numbers to "unknown" I lost all my distinct phone number names on my Google contacts. Fortunately I was able to restore to an earlier Google data point before Apple contacts had changed my Google account, and I was able to restore my custom contacts.
So here is my beef: I think that I should be able to sync these custom fields from Google Contacts since Apple Contacts supports custom fields. I feel as though Apple wants to use Microsoft as the scape goat and Google, not having the best relationship with apple isn't able to do anything about it. The easy solution to me seems for Apple to create a direct sync from Google Contacts to Apple Contacts so that all fields and their names move over to my Apple device. I don't know if the reverse problem exists from Apple contacts to Google contacts but I would say that Google would be responsible to make that happen.
If Apple wants to get more Android users to use their products they need to create a direct sync from Google Contacts (including custom fields) to Apple's Contact format. I'm not going to change over to iCloud for practical reasons and because I will likely always have an android device, I will more likely buy some fApple devices if synchronization is seemless between Google contacts and Apple devices. I await a viable fix to this problem.