To get a copy of your identifier, tap on the menu icon in bitcoin identifier upper left corner. To log into your wallet, you'd use bitcoin identifier Wallet ID, password, plus any form of Two Factor Authentication you've enabled. Like e-mail addresses, you can send bitcoins to a person by sending bitcoins to one of their addresses. On the backup you will see your wallet login link, which includes your wallet identifier in the URL. Making a bitcoin identifier backup helps to ensure you will not lose access to your funds.