John, had smart phones and in particular an iPhone for near 4 years now and there are so many amazing free apps that I've only ever paid for a good guitar tuner, geocaching app and more recently £1.99 one off fee for tapatalk. It basically links all your favourite forums and makes simple navigation and easy viewing, which isn't always possible on the basic browser of a mobile device. This ipad I've just got for Christmas has a pretty big screen but tapatalk is still easier to use.
The only thing that does irritate me is the fact that if you navigate to a forum signed up for tapatalk on a mobile device you get that horrid prompt telling you that tapatalk is available. Sadly, you still get that when you have paid for the App!!