After abandoning its plans to build a student-focused tablet earlier this year, Kno is back, unveiling its new iPad app, Textbooks.

Kno claims that the new app offers the "world's largest catalog of digital textbooks," with over 70,000 titles, many of which are for sale at 30 to 50% off the list price. It also says that the app has "an industry leading set of features" for the iPad.

The breadth of the bookstore and the features of the app are the most important things that Kno needs to nail here if it's going to recover from its hardware failure and become a competitive software company. So how does it stack up?

The Bookstore

Having a vast selection of titles is important, no doubt, as an e-book app-maker wants to be able to get students to purchase as many of their books from them as possible. It has to compete with the brick-and-mortar university bookstore. It has to compete with online book rental companies, like Chegg. And it also has to compete with the likes of Amazon and Barnes & Noble and both their print and electronic offerings.

And Kno has a pretty impressive catalog. Until now, the company that's laid claim to the bragging rights for "largest provider of digital course materials" has been CourseSmart. While it doesn't give an exact number of titles available, CourseSmart says that its catalog includes "over 90% of the core textbooks in use today in North American Higher Education."

That's a distinction worth noting: Kno has a huge selection of educational books, and while CourseSmart does too, the focus of the latter has been on the core curriculum. But with 70,000 titles, Kno is trying to reach beyond that. Kno's titles include a number of O'Reilly books, for example. (the publisher is actually featured there on the Kno bookstore's main page), but it's hard for me to say whether or not these books -- as much as they are indeed the core curriculum for many programmers -- are the core curriculum for many universities. In other words, it's a big catalog, but is it the right catalog?

Nonetheless, it's clear that Kno has a pretty vast selection to choose from, and that's the minimum necessary in getting students to become buyers and users of the app.

The App

While I'm impressed with the catalog, I'm not that excited about the app itself.

The app lets students set up their terms and courses, and then students can drag-and-drop their textbooks into the particular class. Students can also add other documents that are in PDF form so they can, ideally, keep paperwork together. While that's a nice feature in terms of organization, particularly if students are using PDFs from an electronic course packet, but it's not game-changing by any means.

And unfortunately, while you can add PDFs, you can't add books not purchased via the Kno store -- even free, openly licensed ePUBs.

The app contains the obligatory social features. Students can send messages from within the app to Twitter, to Facebook, or to the Kno website. "Hey mom, look I'm studying because this status update originated from an e-book app." That sort of thing, perhaps.

Within the electronic textbooks themselves, students can make bookmarks, highlight passages, leave sticky notes on pages, and perform searches -- within the books or via Wikipedia. There isn't a good way to annotate your highlights, a major drawback.

Osman Rashid, Kno CEO and co-founder, says that The first version of the Kno app ensures that we maintain the consistency and integrity of today's textbook, while making it more engaging, efficient and social. This enhanced digital version gives both students and professors the confidence of knowing that the page numbers, chapters, diagrams and photographs will be exactly the same as the physical textbook, yet a lot more interactive. That's a very different strategy than that of Inkling, another textbooks-on-the-iPad startup that is adamant that the promise of digital textbooks and tablets should offer a lot more than just "consistency and integrity" of faithfully turning a textbook into a PDF. When I interviewed Inkling's CEO Matt MacInnis earlier this year, he spoke about the startup's plan to "gently disassemble the textbook" and to re-imagine and re-engineer what a textbook can look like.

Compared to Inkling (which does have, admittedly, a very small book selection), Kno doesn't feel like it offers anything new. I'm tired of hearing the only argument for electronic textbooks being that we can save kids the burden of "lugging around a backpack full of books." That feels like a pretty big failure of imagination.