Many tablets, smart phones, and eReaders come with their own app for reading eBooks. In order to read books available through other sellers, however, you may need to download another app. Search for apps such as Entitle, Kobo, Amazon Kindle, or Noble Nook to access books through those proprietary services, or to import eBooks in other formats. The Adobe Acrobat Reader app can be used to view any PDF document, no matter where it was downloaded or purchased. Computers are often faster at downloading files, and may have access to online databases that do not function properly on your mobile device. Many devices can be plugged into your computer for quick file transfer, or you can use Bluetooth, iTunes syncing, Dropbox, or email. Some files, especially those purchased from an eBook store, may have DRM protection, preventing them from being opened on more than one device. While mobile phones and tablets can be fine, portable ways to read books, eReaders typically offer an easier way to download books, and more energy-efficient and daylight-visible screens. Keep in mind that many eReaders use DRM protection, which will prevent you from transferring the books to other devices.

TL;DR in Indonesian:
Unduhlah aplikasi buku digital tambahan. Pindahkan buku digital dari komputer Anda. Belilah pembaca digital.