The update adds a new storage management menu, a feature which I'd already been using on the other Kobo iPad app (Kobo Instant Reader). You now have more granular control of the ebooks on your iPad or iPhone; no more having the app download everything. The update also adds the usual under the hood improvements and bug fixes, including an issue where specific books failed to open.
The app also now supports sideloaded ebooks which are encumbered by DRM, and it gained slightly improved support for PDFs (links are now clickable).
And the app now reportedly supports more languages, including French, Spanish, Italian, German, and Dutch. I don't see these as options int he settings menu, but I'll take their word for it. I will note though that they've been selling ebooks in Germany and France for over a year; I wonder why it took so long for Kobo to support their customers?
But what caught my eye was the note about Adobe DE DRM. Kobo's apps didn't used to support Adobe's DRM, so any change is noteworthy.
I know that may sound like an odd reason to keep track of DRM support, but there's a back story here. From what I've heard, the reason Kobo didn't support the DRM was to avoid having to pay fees to Adobe. Instead they used their own DRM inside of their apps, and only used Adobe's DRM with ebooks you bought from them and wanted to take elsewhere.
I'm sure there's a simple explanation for the change; Kobo isn't nearly as cash strapped as they were back when they were owned by Indigo. Rakuten is clearly throwing money at them.
And that's the important detail. Without all that extra money Kobo never really had a shot at competing with Amazon.
You can find the app in iTunes.