Safari 26 on iPhone and iPad makes many websites feel just like apps by...

https://tiny-wiki.win/index.php/Safari_26_Web_App_vs_Regular_Bookmark:_What_Is_the_Difference%3F

Safari 26 on iPhone and iPad makes many websites feel just like apps by improving Home Screen behavior. When you add a site to your Home Screen, it can now open with the new 'Open as Web App' option