You are the only one who will have access to the backup phrase, and you will need it to retrieve your Abra wallet if your phone is ever lost or stolen, or your app deleted.
Your Abra wallet is held privately on your phone. Our company never has access to your funds, or the associated backup phrase. Thus if you lose your backup phrase, you are at risk of losing all funds in the corresponding Abra wallet.
Users are strongly advised to write down their backup phrase, and store it in a secured location, to avoid losing access to their funds.