Go to the Settings tab and tap on Account & Subscription.
Scroll down and tap on Household Users.
Tap Add Household User.
Enter the email address of the person you’d like to add, then press the Done button.
(The person you’re adding must already have an AnyList account. If they don’t, they can download the app and create a free account.)
Note: This must be done in the iOS app as it’s not currently possible to add users to a Family subscription using a Mac or PC.