Being relatively new to using Apple products (got my first iphone a couple weeks ago), I only noticed an interesting feature about the keyboard when using an ipad my wife got this year. This feature is also the same on ipods and iphones.
But first, one of the negatives I've always thought that IDN domains had (and I'm mostly talking about French IDN's here, and similar languages like Spanish which share many common letters with English), was that you needed a special keyboard on your laptop or computer to type them in. The other option was to know the special formula of keys to punch to create each IDN letter. Needless to say, time consuming for the average person - though native users of these languages are likely used to it and are set up for it.
Now comes the ipod, ipad and iphone with their touch keyboards. When you are typing on these keyboards and hold a letter like 'e' down, a display pops up with many IDN options for the letter 'e', such as:
é ê è ë ē
For 'n', you get ñ (Spanish)
For 'a', you see â å æ á
Others for 'c' and 'o' are ć ç and ö ô ø ō
I don't know how many languages the touch keyboard supports (French and Spanish are the obvious ones), but this makes it super easy to create these letters in your words or domains. I wouldn't want to type pages like this (but even in English I wouldn't on an iphone), but to enter a domain name is just about as fast as using regular letters.
The reason I like this is because I own a few two letter .com's, where one of the letters in a french IDN, for example êm.com - another reason is that .ca domains will be enabled for IDN characters (French) early next year. With the touch keyboard, it makes them easier to use. I don't know if Android phones have this same feature, but I imagine they do since it seems like an easy thing to add. It doesn't take away the problem of using laptop and computer keyboards for IDN, but people use smartphones and handheld devices so much these days, that I think it's a significant factor for IDN's.
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