In technical perspective, app should have better user experience than mobile browser.
Mobile web experiences can really be done brilliantly. And I disagree mobile apps should technically have a better experience.
Mobile apps have an advantage that they are targetted to a single platform or experience. Whereas websites work anywhere.
Take my rant with a grain of salt. I'm an old school web developer and struggle when useless apps are pushed when a mobile site would suffice.
Apps IMO have an market advantage that they are fancy bookmarks on people's homescreens.