WhatsApp is considered the world’s most popular instant messaging app, attracting the attention of millions of users worldwide. If we look at the number of

smartphones on which WhatsApp has been installed, it reaches into the millions. It is now arguably the most important app of its kind, despite the many other successful apps with similar concepts.

WhatsApp remains the leader in user numbers. To use it, users register their phone number and then

start messaging. Voice calling was later added to WhatsApp, but its most common use is still instant messaging.

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WhatsApp was created by a man named Jan Koum, who was born in Ukraine. After an economic crisis in the country, he and his mother emigrated from Ukraine to the United States

when he was 16, settling in Mountain View, California. With the help of government assistance, they were able to obtain

They rented an apartment to live in, and his mother worked as a nanny while Jan worked as a cleaner at a grocery store.

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At the age of 18, Jan wanted to learn programming. There were no learning opportunities available, so he had to teach himself. He also couldn’t afford to buy

programming books, so he rented used books until he had finished studying them, then returned them.

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Jan left school in San Jose and went to work at Yahoo as an infrastructure engineer, where he met Brian Acton.

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Jan’s mother died of cancer in 2000. Jan was alone, but he had the friendship of Brian Acton, who was going through a severe financial crisis

at the time after losing his investments in the stock market.

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Jan Koum decided to leave his job at Yahoo. He and Brian Acton shared a dream of joining Facebook, but their applications were rejected in 2007.

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After failing to get a job at Facebook, Jan decided to start his own company. In 2009, he bought an iPhone, when the App Store was still

in its early days. Jan predicted that the App Store would grow into an entire industry of full-fledged apps.

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At a dinner party hosted by Jan and Brian Acton at a Russian friend’s home, they explained an idea for an app that would show users’ status, such as when their battery was about to die,

for example. But they needed an iPhone developer, so their Russian friend introduced them to Igor Solomennikov.

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Jan Koum chose the name WhatsApp because it sounded like “What’s up?” He and Acton then founded WhatsApp in California.
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Jan spent several months working on the code that would make the app work seamlessly with phone numbers around the world.

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Jan gave his friends a beta version of WhatsApp and kept track of bugs and feedback. Eventually, he became discouraged and decided to look for another job, but

Acton persuaded him to wait a few more months to see what happened. Then, in 2009, Apple introduced push notifications, which helped Jan realize

that he had created an instant messaging app.

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Jan released the second version of WhatsApp, and it quickly reached 250,000 users. Acton then brought in five former colleagues

from Yahoo to invest an initial $250,000 in exchange for a stake in WhatsApp.

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Because of the app’s remarkable success, Jan Koum received a series of funding offers, but he consistently turned them down, believing they would jeopardize his dream

of creating an ad-free instant messaging app. But Jim Goetz didn’t give up and kept pursuing them until they accepted him as an investor in WhatsApp. By the end of

2011, WhatsApp had become the top instant messaging app in Apple’s App Store and had been downloaded more than 10 million times on Android.

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In 2014, Facebook acquired WhatsApp for $19 billion in what was then the largest deal of its kind. Mark Zuckerberg, Facebook’s founder, had no idea when Jan Koum

turned down a job at Facebook that one day he would strike a deal with the company to buy an app with millions of users around the world.