If you have an iPad or iPhone, and a friend wants to check out a web site, or your child wants to play a game, you may not feel comfortable lending them the device, since they can access your email, bookmarks, contacts and other personal data.
There's a way to lend a device to someone, however, so they can only access the current app. Go to Settings > General > Accessibility, and scroll down to the Learning section and tap Guided Access. Turn this on, and enter a PIN. Go back to the Accessibility settings, and scroll all the way down: you'll see, in the Triple-click section, that Triple-click Home is set to Guided Access. (Unless you've already set something else for the Triple-click Home setting.)
Now, to lend your device to someone, open the app they're going to use, triple click the Home button, then tap on Start. (You can also set some options before allowing access; tap the Options button at the bottom of the screen.) When the user is finished, triple click the Home button again to exit Guided Access; you'll need to enter the PIN.
h/t Cult of Mac
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