To share a card with another Key Ring user, you would need to do it from your phone.
This also depends on how you want to share cards.
To share all of your cards we recommend that you simply share an account. Download Key Ring on both phones and log into the app using the same account information. All cards will be available on both devices.
To share only select cards choose a card > 'Share Card' > Enter the email address of the recipient.
Note to iPhone Users: If you do not see the share button your settings have likely changed and it's taking you straight to the barcode image screen. You can change the settings on your phone so you see the card information screen first. You do this by clicking on the settings icon on your phone. Scroll down until you see Key Ring listed. Click on that and then you will see the option to change the Default View to see the offers first or see the barcode first.