Cobook doesn’t fix what ain’t broke. It’s essentially Apple’s Contacts app on steroids, with the ability to pull contact information from Facebook, Twitter, and LinkedIn on demand. Cobook can link contact cards with information like a friend’s job title from LinkedIn, location from Facebook, and Twitter handle from Twitter, all without harming your contact files. It might not be the "always synced contact app of the 21st century," but it’s your best option.
Free on iOS