Several stores, including iTunes, offer the possibility of providing the end user (consumer) the option to download a virtual version of an album booklet. This is entirely optional, but will make your release more attractive through added value. 
 
Requirements:
  • PDF format with .pdf extension
  • Four-page minimum
  • No more than 10 MB in size
  • All fonts embedded • 11 in x 8.264 in (28 cm x 21 cm)
  • RGB color • Horizontal presentation
  • All images full-bleed as shown in sample pages 
Important: These booklets are expressly designed for the (iTunes) Store format, and cannot be reproductions of the liner notes with borders to increase their size. 
 
Content Considerations
  • When saving as PDF, make sure the document opens full screen with no negative space surrounding the document.
  • If the digital booklet is many pages, consider using fewer images or optimizing images to achieve lower overall file size.
  • Printer’s marks are not allowed.
  • You cannot sell or advertise other products or services. No other promotional sites are allowed.
  • No links to anything outside of the booklet, except to the artist and/or label website(s).
  • No time-sensitive information (for example, a promotion or dates for an upcoming tour or concert).