A mobile boarding pass is a digital version of the traditional boarding pass designed for use on a smartphone, tablet or other smart device such as an Apple Watch. This digital boarding pass, sometimes called an e-ticket, is represented by a barcode that you can retrieve and scan via an app.
Replace paper with mobile boarding passes
Airlines and other companies that support e-tickets and digital boarding passes will often send you the relevant barcode in an email. In this case, the barcode image is usually displayed in the body of the email itself or in an attachment, such as a PDF file.
Some airlines use a mobile boarding pass that looks exactly like the paper version, while others use only a barcode.
The barcode can be a regular rectangular or a square QR code. Many companies direct you to click on a link in the order confirmation email to view your boarding pass on the airline's website or app.