Better contact management: WhatsApp saves contacts directly in the app

In the future, WhatsApp users will find it easier to manage their contacts on a cell phone. As the company announced in a blog post on Tuesday, contacts will in future be stored locally directly in the app. Previously, it was only possible to use contact information via the internal address book of the cell phone in WhatsApp.

Until now, WhatsApp has relied on the cell phone's address book to store, manage and synchronize contacts. This is problematic if a user loses their smartphone and has not backed up their contacts. The contact information cannot then be reconstructed in a new WhatsApp installation. There can also be difficulties if several people use one phone together or for anyone who wants to manage several accounts with separate contacts on one cell phone.

Local storage and synchronization with the WhatsApp cloud

In the future, WhatsApp will circumvent the problem by storing the contact information locally on the device and synchronizing it with the WhatsApp cloud. If the cell phone is lost, for example, the contact data can then be retrieved from the cloud on a new device and is then available to the user again. This is also possible if the smartphone is changed. The same also applies to other devices on which WhatsApp Web, the apps for Windows or macOS are used. The saved contacts will also be synchronized with this in the future.

WhatsApp uses a new encrypted storage system called Identity Proof Link Storage (IPLS) for storage. When a contact is saved, the system generates a key on the device. When a contact is retrieved, the client uses it to authenticate its identity. The app also works with the services of the internet security company Cloudflare. All changes to the cryptographic properties of the user directory are signed. In this way, WhatsApp wants to ensure that no one has changed the contacts stored in WhatsApp.

Storing the contact data locally also allows it to be better organized. For example, it is possible to manage personal and business contacts separately if more than one WhatsApp account is used on the device. In addition, contacts can now be saved and managed by the user's name. It will no longer be necessary to enter a phone number when a contact is to be established. This is then possible by entering the username.

Newly created contacts in WhatsApp can be synchronized with the cell phone's address book. WhatsApp provides a corresponding button in each contact for this purpose.

The new functions will be available in the coming days and weeks in the apps for Android and iOS as well as WhatsApp Web, the apps for Windows and macOS.

(olb)