The WhatsApp platform will be working on a new tool to verify user accounts: automatic calls.
Users can choose to receive a call instead of an SMS when an account verification is required. The user will receive a call that will last for a few seconds (no answer required).
WhatsApp will then check the call history, comparing the call made with the last entry in the history.
The tool will be released only for Android as iOS does not allow applications to access the call history, something that will need to be activated for this feature.