1. you can do much more with interfaces and processing power in native mobile. Even simple apps like piazza or quora, I can't see being implemented nearly as nicely in the web. People think it is all about animations, but it isn't. A small example is how the entire web page has to be loaded each time you click a link on the hacker news mobile site or hit the back button or anything. A mobile app on the other hand would load all the links when you first open the app and when you hit the back button from looking at a link, you'd be met with zero latency.(not to mention persistent settings)

2. With my iPhone at least, I enjoy the predictable user interface that comes with doing stuff inside IOS.

3. I'll be honest. I don't like typing in URLS on my phone, and typing in passwords. It is a real pain when alternatively I could just click an app.

4. I really hate the mobile sites for some companies. The mobile site for my school is awful and always redirects you to some ugly main menus from the page you actually wanted. I would much rather just have the regular website.

One example - I use the ebay app on Android over the web site. It's miles better due to native integration. It remembers my login better than websites do (probably a security risk, but my phone's encrypted), it integrates photo-taking direct into the app which is handy for selling and buying e.g. buying: if you have a minor dispute with a seller you can just blast off a photo in the built-in messaging system. It sends notifications for watched items. The UI is also better than the mobile site - the click targets are nice and big and the lists scroll quickly - but that could possibly be improved in the site. The native integration is mostly what makes it nice.

i'm not saying web dev isn't easier to deploy for multiple platforms. I'm saying native is much better to use from a user side.