Meta is introducing WhatsApp ads on a rolling basis. Privacy experts raise the alarm, despite WhatsApp's assurance that end-to-end encryption remains.

They will appear in only one part of the Meta-owned messaging service, it said. The move is potentially lucrative, while raising questions about user privacy.

As Meta prepares to build an ad-driven future for WhatsApp, the app’s strong record of privacy-focused design is about to meet a familiar marketing problem: the infamous ad fatigue. Can Meta monetise WhatsApp without tiring out its two billion users?