Why shortcut apps exist in smartphone?

My company is making a shortcut app(aka "glorified bookmarks") for smartphones, which is just a browser directly linked to one of our web pages.

I can't understand. Technically, Web apps can be accessed via mobile browsers, which is included to all mobile OSs. Shortcut apps seem redundant to me.

I'm not an app developer(I'm a web developer btw), but I also heard it is hard and takes a long time to submit apps to app stores, especially in iOS since their policy forbid this kind of apps. To workaround this, our iOS app has a foldable dock containing some links that web app has. Too many hassles for a small thing.

My only guess is, it is easier for customers to use shortcut apps rather than using mobile browsers and googling to find our websites and bookmark them.

Why shortcut apps exist? Is this a good/bad approach? What are the alternatives for better UX?