# Preference Center Opt-In Support for Email and SMS

Grow your email and SMS audiences from your app's Preference Center. Users can self-manage their email addresses and phone numbers alongside their notification preferences.

In an App [Preference Center](https://www.airship.com/docs/reference/glossary/#preference_center), now you can add notification opt-in prompts for Email and SMS. Just like our App and Web opt-in prompts, they appear as embedded banners within a Preference Center. All labels and fields are fully customizable.

![Opting in to SMS in an App Preference Center](https://www.airship.com/docs/images/whats-new/pf-sms-opt-in_hu_353b6085d81efdde.webp)

*Opting in to SMS in an App Preference Center*

Opted-in addresses and phone numbers associated with a [Named User](https://www.airship.com/docs/reference/glossary/#named_user) are listed within the banner. Addresses or numbers added by the user are automatically associated with their Named User ID, allowing for cross-channel messaging.

Users can add email addresses or phone numbers in order to opt in, add other addresses or numbers, or remove their contact information in order to opt out. They must complete the [Double Opt-In](https://www.airship.com/docs/reference/glossary/#double_opt_in) process in order to start receiving messages.

## Requirements and documentation

Required for Email and SMS opt-in prompts: [iOS SDK 18.6+](/docs/docs/developer/sdk-integration/apple/ios-changelog/#18.6.0) [Android SDK 18.1.2+](/docs/docs/developer/sdk-integration/android/changelog/#18.1.2)

Get all the details about [notification opt-in prompts](https://www.airship.com/docs/guides/messaging/features/preference-centers/#notification-opt-in-prompts-and-contact-information) and [how to configure them](https://www.airship.com/docs/guides/messaging/features/preference-centers/#configuring-opt-in-prompts-and-contact-information) in our *Preference Centers* user guide. Learn how double opt-in works for [Email](https://www.airship.com/docs/developer/api-integrations/email/getting-started/#double-opt-in) and [SMS](https://www.airship.com/docs/developer/api-integrations/sms/opt-in-out-handling/#double-opt-in) in our platform documentation.