If anything, I might suggest buying an Android tablet, instead of a specialized e-book reader. I realize the Kindle can do a good bit, but then you can have an Android tablet, which can essentially do the same, and more.
But in-short, what does this have to do with Japanese learning? Well, a Kindle (afaik) is locked only to Amazon's app store (unless you go out of your way with flashing, rooting, etc). Then there's an Android tablet (like the Nexus 7), which has access to Google Play Store (which is larger on its own), and Amazon's app store if you choose to.
I have no idea what apps, formats, or anything is on the Kindle, but there's plenty of e-book readers available for Android.
But in-short, what does this have to do with Japanese learning? Well, a Kindle (afaik) is locked only to Amazon's app store (unless you go out of your way with flashing, rooting, etc). Then there's an Android tablet (like the Nexus 7), which has access to Google Play Store (which is larger on its own), and Amazon's app store if you choose to.
I have no idea what apps, formats, or anything is on the Kindle, but there's plenty of e-book readers available for Android.