The most recent big iOS update, which makes it easier to opt out of ads that track you across apps and web sites, has sent the digital marketing industry into a bit of a tizzy. That includes Facebook, which has been telling users that tracking helps keep its services "free of charge." Facebook is doing just fine, and choosing to preserve your privacy is not going to result in an Instagram service fee. Elsewhere in social media privacy news, Twitter rolled out a so-called Tip Jar this week that lets you send money to your favorite users. But it failed to vet how PayPal handles payments, potentially exposing users' home or email addresses when they send or receive a tip.