Updated 25 October 2023 We have stopped onboarding new agencies to using the pre-call notification feature.
Notify the MoP before calling using the official Gov.sg WhatsApp channel - the successor to CheckWho, a previous OGP product to enable officer verification.
On Postman, as a government agency user, you can use this feature to send an official message ahead of time to let residents know about your upcoming call directly via the Gov.sg Whatsapp, so that they will know who you are and why you are calling.