For the latter, bills have been paid long ago (sunk costs), titles are carried in inventory at or close to zero cost, and direct mail campaigns will create a low cost of goods sold and will be able to sustain a lower rate of response.
A browser is software that is used to access the internet. A browser lets you visit websites and do activities within them like login, view multimedia, link from one site to another, visit one page from another, print, send and receive email, among many other activities.
Is the iPad's Safari web browser not exactly your cup of tea? While Apple requires all web browsers on the iPad to use the WebKit platform, there are actually a number of great web browsers that can be used as alternatives to the Safari browser.