Downloading textbooks to your digital device

Going back to school means filling a backpack or - more and more often - a digital device with textbooks. Here are some ways to get that chore done with smartphone applications.

Amazon Student, by Amazon Mobile L.L.C. for Android and Apple, is one of many free apps from the online-retail powerhouse. This one is tooled for school, with an image of a satchel of books gracing the home screen. Amazon lets you scan a bar code to buy or sell textbooks - except, of all things, Kindle e-books from Amazon.

When you scan any item, you can compare prices, and you can share the information via e-mail, text message, Twitter, or Facebook, or with a few taps, add the item to a "wish list" or shopping cart.

Signing up for the Amazon Student service, using an ".edu" e-mail address, qualifies you for six months of free shipping, along with selected deals and other promotions for students.

With the trade-in feature, Amazon buys used items, including textbooks, but only in exchange for credit on Amazon - in the form of a virtual "gift card" deposited to your account. (Some users complain the offered trade-in prices are low.) It's good for unloading old movies, games, and electronics, too.

Half.com, from eBay Mobile, is another place to buy and easily sell textbooks and other media titles, using bar-code scanning and other tools that simplify the process.

Kindle, the Amazon e-reader, comes as a free app for most devices. With many textbooks now available digitally, there's a good chance your books can be purchased or even rented for reading on a tablet or smartphone at a discount to the print version.

But the Amazon shopping apps tell me they don't support Kindle downloads. Instead, I was directed to add the desired Kindle books to my Amazon wish list, then complete the purchase at the Amazon website.

If you already own Kindle books on one device, they will be available for download to another device with the app.

For boning up on your language studies, Learn Spanish is one of the language-learning game apps from MindSnacks, which also has apps for learning or refreshing your Italian, French, Portuguese, German, and Mandarin (as well as several apps for learning English). Each app is free for one level of the learning game, and $4.99 for a full upgrade to 50 levels.

The games are repetitive and addictive and, if you like, will report your score to your pals on Facebook and Twitter.