Update: Keep in mind that your app must first request permission to access the contacts list. I used TDPFAddressBook to do that in my production project and here is the code.
Access IOS Contacts With Firemonkey in Delphi XE5
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Update: Keep in mind that your app must first request permission to access the contacts list. I used TDPFAddressBook to do that in my production project and here is the code.