All standards are learned. What Jakob nielsen misses is that the touch interface is a new paradigme because it removes abstraction from the interaction. You can't judge it on old metrics that themselves in so many ways are wrong and clumbsy.
Jakob nielsen is wrong and have been for a long time. Usability isn't any longer a field to be taken serious in itself. Only when paired with actual design skills does it start to make sense. As a qualifier not as a discipline in itself.
I've said it before. In five years from now usability is nothing more than another tool in the designers box on the line of grid systems typography etc.
When you say "Neilsen is wrong", you really need to back that up. The Neilsen/Norman group conducts empirical studies and has a fair amount of transparency about their work. Most of the "professional" web designers I've worked with tend to favor their design over the user's needs. I would agree that Neilsen advice falls into the conservative design camp more then I appreciate, but at the very least he has actual metrics and user testing to draw his conclusions on. Having been in multiple user testing sessions and seen many a fancy design go down in flames of user confusion, I'll believe that "usability is nothing more then another tool in the designers toolbox" when I see it applied more consistently.
I don't think anybody that knows about Usability Metrics takes "Neilsen" that seriously. Neilson is more popular with the 5 user is enough camp while most people dealing with Ux Metrics believe that you need to be testing with at least 50 to 300 users.
He does NOT say that you should stop testing as soon as you have testing with five users, but rather that you should build usability testing into your development process throughout all of its stages, but especially the early stages.
We have moved along way since the simplistic rule of thumb that 5 users is enough. A very good argument in why 10 is not enough is Woolrych and Cockton 2001. They point out an issue in Nielsen formula (1-(1-0.31)^5) in that he does not take into account the visibility of an issue. They show using only 5 users can significantly under count even significant usability issues.
The number of users you need is dependent on how many issues there are, the cultural variance of your user base, and the margin of error you are happy with. Five users or even 10 is not enough on a modern well designed web site.
For example if we assume that designers of a web site have been using good design principles and therefore an issue only effects 2.5% of users. Then 10 users in a test will only discover that issue 22% of the time. If your site attracts a 1 million visitors a year the issue will mean that 25,000 people will experience problems.
The easy way to think of a Usability Test is a treasure hunt. If the treasure is very obvious then you will need fewer people, if less obvious then you will need more people. If you increase the area of the hunt then you will need more people. Most of the advocates of only testing 5 to 10 users, experience comes from one country. Behaviour changes significantly country by country, even in Western Europe. See my blog post here :
It's the normal difference between quantitative and qualitative research. This kind of study is of the exploratory kind, capturing what's going on while the users interact with in this case the iPad for a while.
This study is very useful to use as an UX designer, to see where the potential hazards and weak spots in your design is.
Jakob nielsen is wrong and have been for a long time. Usability isn't any longer a field to be taken serious in itself. Only when paired with actual design skills does it start to make sense. As a qualifier not as a discipline in itself.
I've said it before. In five years from now usability is nothing more than another tool in the designers box on the line of grid systems typography etc.