The success of WhatsApp was key to holding on to our values during our transition from 20 million to 1.2 billion users, supported by a unique engineering culture that focuses on simplicity and prioritizes core features over many tasks.

The acquisition of WhatsApp was surreal; I struggled to comprehend the magnitude of a billion dollars and what it meant for me personally.

At WhatsApp, we focused on core utility features like messaging and calling, rather than gimmicks, to ensure quality and reliability.

In the mobile era, Apple was ahead while Facebook struggled to keep up, often acquiring companies like Instagram and WhatsApp to strengthen its position.

WhatsApp and Instagram, both small teams at the time of their acquisitions, leveraged Apple's platform to achieve significant growth and impact.

I was the 19th engineer to join WhatsApp, and we had around 20 million users at that time, which grew to 1.2 billion active monthly users by the time I left.

Historically, companies like WhatsApp and Instagram have been close to achieving unicorn status with very few employees, but a sustained trend of this nature has yet to be established.

Facebook's success was due to secure connections and ensuring that new users had at least 20 friends on the platform, which made it more engaging.

One key to startup success is not being overly driven by immediate financial gain; Mark Zuckerberg's decision to decline a billion-dollar acquisition offer from Yahoo exemplifies this principle.