If something can be done through a web page, why is it being done through an app in the first place? Most of the time it is so that updates can be pushed and the app can be doing more than it really needs to do to deliver the service.

For things like this, you just need to sign up and put in a little bit of info, but now you have to install and app that may or may not be hugely bloated, require permissions you it doesn't need, push updates frequently, etc.