O WhatsApp announced that it plans to introduce a new security feature to the messaging app, which will allow users to hide their mobile phone number from other users.
The WABetaInfo website says that this feature will be specific to the Community area, where users can interact with unknown people. Given the fact that having access to unknown people's numbers can lead to unwanted contacts and even harassment, this is an option that will certainly be well received by users.
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This security option is only present for users of the beta version of WhatsApp for Android, so it should be available soon for all users of the app.