Use Guest Mode to block your email, texts, etc. from view when a friend uses your phone.
1 Swipe down to open Quick Settings.
2 Tap the user icon on the top right and select "Add a Guest" to start Google Guest Mode. Your phone will switch to the guest mode and your information will be protected.
3 When you get the phone back, end Guest Mode by tapping the user icon and selecting "Remove Guest."
4 Tap "Remove" to delete all apps and data from the guest's session.