Application lock for iphone

I have tried to go around the web finding an answer to this myself. But I found nothing. Is there a special reason why apple is not providing a simple option to lock certain basic applications like messages, photos, browser and most importantly the settings. This is a very simple thing to expect which is available in a starting range basic phones of certain other brands.

I did find some people recommending restrictions as an option to similar questions asked earlier.

People don't expect to hide an application they just want to lock it for safety.