Why do barcode scanners on android display the last digit if it's a checksum?

Question

Android

It is necessary to encode the phone number for the badge for quick registration.
Wanted to do on EAN13. It seems that everything is normally encoded, but a digit is added at the end, I read it - a checksum. There is no trading scanner, I tried to scan from my phone. And for some reason, all the applications that I tried stubbornly display this last digit in the result. Why and how to overcome? Can another type of barcode be used ... has anyone done barcodes on badges? You need exactly one phone for registration, and not a qr-business card.

Answer 1

Almost all barcodes contain a checksum to check the correct reading. To use it when reading or not, to transmit to the output or not to transmit - this is the scanner setting. In principle, no one bothers to manually generate a barcode without adding a check character, but reading it by scanners is not guaranteed.
For a phone number, it is better to use not EAN-13, which must contain exactly 12 digits + a control, but Code39, which has an arbitrary length and an optional control character.