In my search for the perfect CRM, I have tried more then I care to mention. When I cam across Prosperworks and their claim of "zero" manual entry I was skeptical to say the least. However once I set myself up for the 14 hands on experience I was impressed. The app scans your email and looks to see who you contact and how often and recommends you add them to your contact list if you haven't already. Google emails and related items are automagically added to contact details and kept up to date. The contact sync is through PieSync if you need two way or through the application itself for one way but that's a minor item. Give it a try, I think you'll be impressed.