Many e-books can be read through simply the device's web browser. Others will require dowloading an app to your Android or IOS (ipad, iphone, ipod touch) device:
Most downloadable electronic books (e-books) are in a pdf format with digital rights management (DRM). E-book publishers and providers vary widely as to what downloading or printing rights are allowed (by chapter, by percentage, by page limit). Entire e-books that can be downloaded are usually "loans" and the downloaded e-book will time out after a certain period. Other databases (see HathiTrust) may allow downloading and retaining the whole book in some cases.
The main KU subscription e-book providers, EBL, EBRARY, and EBSCOHost. EBL and EBRARY allow the option to either view online or download directly to a mobile device that supports Adobe Digitial Edtions DRM. EBSCO ebook dowload option is incorporated into its platform, and does not require Adobe Digital Editions or other application.
Adobe Digital Editions is currently natively supported on Sony Readers and newer Nook readers. Adobe Digital Editions DRM is also integrated into the Bluefire reader app (free download) for Android and IOS devices (Ipad, IPhone, Ipod Touch)*.
*Please note that trying to download and read e-books on a smaller device such as the Iphone or Ipod Touch with Bluefire may result in text that is too small to read comfortably. These e-book platforms typically use pdf formats that do now allow resizing of the text.