There are a number of reasons why you'll need to know what version of Apple's iOS your iPhone is currently running. Finding out is as easy as:
- Open the Settings app
- Tap 'General'
- Tap 'About'
- Scroll down and look for 'Software Version'
The value specified in 'Software Version' tells you what version of iOS you're currently operating.
Moving apps around on the iOS home screen has always been done with "wiggle mode". Once the icons are wiggling, they can be rearranged or deleted. Apple changed the process starting with iOS 13.
To delete apps or reorganize the home screen using iOS 13 or later:
Instead of long pressing an app to get it to "wobble" and then going through all of your screens and folders tapping the "x" on apps you want to delete, you can accomplish the same thing much more quickly via the App Store. Just open the App Store, tap on your profile/account button, then scroll down through your recently updated apps. Swipe left on any app you want to delete and you will see a Delete button.
The dock at the bottom of your iPhone or iPad's Home Screen is where you keep (or should keep) apps that you use frequently, because the dock is always on your screen, regardless of which page of apps you've swiped left or right to. It only fits four apps and most of us use more than four apps on a regular basis, so fitting more on the dock would be useful. You can accomplish this to a degree by using a folder in your dock. It might not be worth it if you only have a couple Home Screens worth of apps to swipe through, but it probably is if you have many many pages of apps and folders.