Jumbo
It's becoming increasingly clear that basically nothing you do online is private, but Jumbo can at least help you get a handle on what's readily available to prying eyes. This free app will automatically delete old tweets, clear out your Google search history, and get rid of any old Alexa recordings. In addition, it can go in and change your Facebook privacy settings so that you're the only one who can see most of your info while turning off creepy facial recognition and restricting ads. In short, it's the best thing you can do for your social media privacy, next to deleting your accounts altogether.