[mgmueller]

As a reader, Microsoft Surface unfortunately only is a mediocre experience.

Kindle: Strange. I've got the 64GB Surface and still plenty of free storage. Still, after downloading maybe 50 eBooks (original purchases from Amazon) I've got the error code "not enough storage. Delete some books...".

I had this on Kobo touch before. But here simply the reason had been the huge Dilbert files, ca. 50MB each. So I actually ran out of space...

Else, the Kindle app is about what you'd expect. No complaints - with the exception of the storage issue.
Well, maybe another minor issue: Some books (maybe 10% of the ones I've tried) aren't available yet for Windows 8.
For now, I've deleted all Kindle books from the Surface. I'll only download my 20 momentary favorites when traveling, whereas usually I'd take all books with me.
Well, I've got the Kindle Fire HD for that...

Kobo: Extremely disappointing. I've only tried downloading my original purchases, no sideloading. Text books are fine. But some big files, i.e. my Dilbert and Garfield cartoons = ca. 50MB each, crash at the end of the downloading process. When restarting the app, the books haven't been downloaded. I've tried both the US and the German app. Same result. I hate issues like that: I'm using the original books in the original app. How can this make the app crash?

Zinio: Very strange downloading process.
I can scroll through my library. Lots of old issues missing - okay, I can live with that.
Normally, I'd see in my library what's on the unit and what's still in the cloud.
Here I don't!
In the settings, I define "automatically download all magazines from the last 120 days".
There's a status bar, showing the download progress of the respective magazine.
But whether a magazine has been downloaded or not - I simply can't see it without opening the respective magazine.

Else it would be great. Finally bookmarks again! Really had been missing them on iOS and Android.