I've used the Guided Access feature on my iPhone for when the grandchildren want to play with it. I have some games that one grandson really likes, but although he's only 17 months old, he knows perfectly well how to use the Home button to get out of the game and get to the rest of the phone.
That is why I use the Guided Access (triple-click Home) feature to lock the app and protect areas of the screen. If you have an iPhone and aren't familiar with this, it's Settings > General > Accessibility > [Learning] Guided Access. Once you set it up, you triple-click Home to activate it, and triple-click Home and enter the passcode to turn it off.
My daughter taught me that one. And, I use it when I let my youngest play on the iPhone. I also stay with it and watch, so he doesn't hide it behind the couch or flush it down the toilet. I mean, he's 17 months old. That what boys that age do.
So, I am thankful that my daughter taught me that trick. I'm thinking that she should have taught her husband the same trick. Because the boy got hold of his father's iPhone. Here's how it looks now:
Yes, that's in November 2057, nearly 44 years from now. Do the math if you don't believe me. (And just why don't you believe me?)
The child got his intelligence from his parents. And his sense of humor from his grandfather. I am so proud.