Here we go, right off the bat , the central piece of technology in H2G2, the book itself, is an e-book a good 29 years before the release of the Kindle (yes, the Kindle wasn't the very first e-book, but it's certainly one of the most popular). The guide itself is described as similar to a laptop computer with a hundred buttons and a screen that measures around three to four inches (and with the words "Don't Panic" inscribed on it in large, friendly letters on the cover - that's very important).
The fact that Amazon don't currently appear to sell a "Don't Panic" Kindle cover is surely some kind of travesty. However, there are a few Etsy sellers lurking in the bowels of the internet that will happily knit one for you.
Unfortunately, many modern equivalents of the Guide aren't quite as hardwearing as the original, which is described as surviving everything being hurled into prehistoric rivers to frozen on the glaciers of the moon of Jaglan Beta. Perhaps someone should pass that on to those lovely people at Apple, it might encourage them to produce a screen that doesn't self destruct at the slightest tremor.