App icon not changing after updating App

I was facing this issue and none of the provided answers here or somewhere else helped me so I did next steps.

For X-Code 8+

I've opened my project viewer

Then I've chosen Assets

Right-clicked there and I've chosen App Icons & Launch Images -> New iOS App icon

Attach the images, that you want to resolutions of your app icon in your newly created AppIcon asset (rename it as you want)

Then go to the project settings and choose new app icon there

It worked for me

If I uninstall the app, restart the phone and then install the app again, it works correctly. I think some issue with the app cache.

Use "Build > Clean all Targets" and then build and run. Xcode doesn't always see that images have been updated, and leaves them out of incremental builds. Cleaning before building makes Xcode build the app file from scratch, and will pick up any images it's failing to get.