The Origami Cover lacks an integrated keyboard. So to use the Kindle Fire HDX as a productivity machine, you'll need to make do with the software keyboard, or tote a separate Bluetooth keyboard whenever you want to get some work done. I really appreciate the Microsoft Surface for its integrated keyboard covers, so the lack of an integrated hardware keyboard is a strike against the Amazon tablet.
Of course, keyboards don't make any sense when carrying a smaller tablet around by hand. For these scenarios, you'll want a stylus.
For actual handwritten note-taking, I recommend one of two inking apps: either Handrite Notes or 7Notes. Both are available in premium and free versions. For digital inking, I prefer Handrite Notes, which allows you to scrawl notes in whatever size and orientation you prefer. Every time you lift your hand, the software then automatically resizes the word (or group of words), placing it just after what was previously written.
7Notes--specifically the $7.99 Premium Edition--includes a handwriting-to-text engine that can turn your notes into usable text. The latter also exports to Evernote and a number of other services.
It's Amazon's world, and you're living in it
Amazon has largely cut off the Kindle Fire HDX from the Google ecosystem, including the Google Play Store. On the positive side, Amazon offers most of what the Play Store offers (at least in terms of tablet apps), and it also offers one premium paid app per day, for free. So, if you're vigilant, you may be able to pick up what you want without paying. Amazon also offers Kindle Fire users 500 Amazon Coins--a digital token that can be traded for cash, one Coin per cent at press time.
On the negative side, Amazon makes it difficult to access Google Drive and other services within the Google ecosystem. If necessary, you can sideload these apps onto the tablet. The easier way is to use Google's own mobile sites to access these services. The limitation with this approach, however, is that you can't really download a Word file stored in Drive to your tablet. Instead, it will download as an HTML file, albeit with formatting preserved.
If you want to avoid Google Drive altogether, documents can be loaded onto the Kindle Fire HDX via a few other methods: by connecting a USB cable and physically transferring them; or storing a Web page for later perusal, or emailing them to yourself through what Amazon calls the Kindle Personal Document Service. The latter capability stores and converts Office documents for you, but it's a legacy feature that you won't really need with a modern Android office suite, such as the OfficeSuite Pro app that's included with the tablet.
Sign up for CIO Asia eNewsletters.