I know we all love our iphones its a nice phone to have. But consider a scenario were your iPhone gets stolen and the thief somehow gets your passcode, changes it and locks you out of your icloud account for life!
The nost annoying thing is when this happens Apple can do absolutely nothing when the real owners contact them to have access or retrieve their lost icloud accounts in the name of security and privacy concerns.
If you are currently using an iPhone, get and android phone or make sure you try using other cloud services to store your photos and personal information, such as: Google photos, Google drive etc.
When you are in public and you want to type a passcode, make sure you dim the light on the phone screen or simply switch to using finger print to unlock your device which I normally use. Ensure you have a very firm grip of your phone whenever you're using it publicly.
Stay save guys.