'Accept all' federation address allows you and other users to receive any Stellar assets without manually adding trustlines for each one - LOBSTR takes care of that for you.
You can safely use and share this unique alias with others.
Once you receive an incoming payment for an asset you don't have trustline for, all you need to do is simply choose to claim or cancel the payment inside your LOBSTR wallet.
Each LOBSTR user has an 'Accept all' federation address, created using the email address of user's account, enabled by default after sign up so you can immediately start receiving tokens.
Additionally, you can connect your personal mobile number to your LOBSTR account on the Settings page and share the corresponding federation address with others to receive funds.
You can find your 'Accept all' address or disable the 'Accept all address' functionality in the Wallet section of the Settings page.
To learn more about sending assets to email addresses or phone numbers and how 'Accept all' addresses help with that, follow this link.