You can use Guided Access to limit your iPhone to a single app, and control which features are available. Once you start a Guided Access session, you can hand your device to someone else without letting them access all your other apps and personal information.

To learn more about this topic, visit the following articles:
Use Guided Access with iPhone and iPad: https://apple.co/3FGY5tP
About the Accessibility Shortcut for iPhone and iPad: https://apple.co/38vtdQB
Apps, settings, and features that you can use from Control Center: https://apple.co/3JRIeLY

Additional Resources:

Get Support for iPhone: http://apple.co/iPhone

To subscribe to this channel: https://www.youtube.com/c/AppleSupport

To download the Apple Support app: http://apple.co/2hFtzIv

Apple Support on Twitter: https://twitter.com/AppleSupport

To check coverage directly on your device: https://coverage.apple.com/ac4N1XV

For more videos, go to Youtube Apple Channel