Instapaper is one of the few iPhone apps that I consider absolutely indispensable. For anyone who hasn’t heard of it before, the description for the app (and web service) is: “A simple tool to save web pages for reading later.”

Great things about Instapaper:

• clean, simple user interface
• it doesn’t require a network connection at all times (which means I can read all those interesting blog articles I saved whilst on the Tube.)

It’s like carrying the best bits of the Internet in your pocket.

The author of Instapaper, Marco Arment, revealed a preview of Instapaper for the iPad. It’s looking pretty awesome. One of the things that resonated was Marco’s use of paper prototypes for designing the app. In fact, it saved him a load of time and development effort:

So, rather than rewriting my entire interface for the iPad over the two months that we’ve had, I spent the first few weeks finishing and launching the 2.2 update to my iPhone app, a major undertaking that added a lot of great features, using techniques that would allow me to easily adapt all of the features to the iPad. And I spent the remaining time adapting my interfaces, rewriting or modifying where necessary, for this new platform.

I’ve got more to write about paper prototyping (and prototyping in general), but the above is a perfect example of the strengths of this technique.

In a related note, I know some developers are scrambling to get some apps out in time for the iPad launch. I have to say I am sceptical of the quality of a product not tested on hardware. In Instapaper’s case, a conservative approach to development makes me think it will be a successful launch. As for other apps, it will be interesting to see just how good or bad they are.