Galaxy S4 just updated to latest Android and now my email is previewed on my lock screen. Any way to turn this off? I'm using Gmail. Thanks
Go into Settings > Sound & notification > "App notifications" and set Gmail as sensitive (as shown here: https://youtu.be/GNFE-S42wgU )
If you want to prevent all apps from showing notifications on the lock screen go into Settings > Sound & notification > "When device is locked" and set "Don't show notifications at all"