Digi-cards is now compatible with all e-book software and devices making them the most efficient and last physical distribution option. Since the first catalogs where distributed more than 3 years ago making Digi-cards an eco-friendly, efficient and inexpensive replacement of distribution of paper products, many advances in e-book technologies have come and gone. Digi-cards has always been in the cutting edge of those technologies by testing and upgrading our systems to make them available to all publishers, independent or not. Digi-cards can carry everything from the most popular IDPF/EPUB .epub to the all of the following; .aeh, .djvu, .fb2, .html, .azw, .lit, .prc, .exe, .pdb, .txt, .pdf, .ps, .rgo, .tr2 and .tr3. Digi-cards also work in all of the following readers and operating systems: Kindle (All), Android, Apple, Azbooka, Nook (All), Bookeen Cybook, COOL-ER, GNU/Linux, Foxit eSlick, Hanlin e-reader, Hanvon WISEreader, iRex iLiad, Iriver, Kobo, Nokia, NUUTbook, OLPC XO, Onyx Boox, Mac OS X, Windows, Pocketbook, Sony Reader, Viewsonic VEB, Windows Phone 7. In addition, another benefit for publishers is that they can receive the official “Saved trees” logo from www.Digi-green.com, letting their readers know how many trees they saved by purchasing the Digi-cards in lieu of a paper book.