Android/iOS: You don't need a PhD to understand Facebook or Google's privacy settings, but it might not hurt. If you'd like a faster way to figure out which buttons to uncheck, AVG PrivacyFix can tell you which settings you need to adjust.
Once you use the app to log in to your Facebook, Google or LinkedIn accounts, it will return a report on which privacy-related settings may need to be adjusted. Keep in mind that some of these settings may disable or affect features you want (like Google Now), but if you haven't done a good privacy audit recently, this is a great place to start — and it's free.
AVG PrivacyFix [iTunes App Store]