iOS Security Flaw Opens iPhones to Data Mining →
Don’t install apps from third-party sources other than Apple’s official App Store or the user’s own organization. Don’t click “Install” on a pop-up from a third-party web page, as shown in Figure 1(c), no matter what the pop-up says about the app. The pop-up can show attractive app titles crafted by the attacker. When opening an app, if iOS shows an alert with “Untrusted App Developer”, as shown in Figure 3, click on “Don’t Trust” and uninstall the app immediately
Btw, this suggestions must already be embedded to every user’s common sense.