The calculator makes sense because there's no need for you to be online when using it - this is more about things that absolutely require Internet access to run (a currency convertor is sort of in the middle, depending on whether you need it up-to-the-minute or not). The page loading is... I suppose not something I'd seen as a huge issue, but yes, with the interpretative part of an application already on the phone, data transfer could be reduced a massive amount.