WhatsApp typically relies on the smartphone address book it runs on to hold and manage contacts. But that can be a problem for users who lose their device and fail to back up their phone’s contacts, people who share phones, or those who manage multiple accounts with separate contacts on one device.
To start, you’ll be able to save contacts on WhatsApp Web and Windows and Meta says that you’ll “eventually” be able to do so on other linked devices. Contacts saved in WhatsApp use a new “privacy-preserving” storage technology called Identity Proof Linked Storage (IPLS) that Meta explains keeps names and numbers encrypted and can only be accessed by the user.
In an email to The Verge, press representative for WhatsApp Jessica Maskell wrote that the new contacts feature will be followed by a new username system where phone numbers won’t be required. Other end-to-end encrypted messaging apps like Signal have also added a phone number-free option for using the app.