50 Fun Facts About WhatsApp

WhatsApp's two founders, Jan Koum and Brian Acton, had both previously worked at which internet company?

They both applied to work at Facebook after leaving and were rejected, five years before Facebook paid $19 billion for their app.

The name WhatsApp was chosen because it sounds like which phrase?

Jan Koum incorporated WhatsApp Inc. in California on February 24, 2009, a week after settling on the name and, as it happened, on his 33rd birthday.

What was WhatsApp originally designed to do before it became a messaging app?

When Apple launched push notifications in June 2009, users began pinging each other with jokey custom statuses like 'I woke up late', and it turned into instant messaging almost by accident.

In which month and year did WhatsApp first appear on the Apple App Store?

A BlackBerry version followed the next month, and Koum nearly quit when the early builds kept crashing until Acton told him to wait a few more months.

How much seed funding did Brian Acton raise from five ex-Yahoo colleagues in 2009 to become a WhatsApp co-founder?

He officially joined the company on November 1 that year, having earlier been working on a different startup idea.

Which company made multiple offers to buy WhatsApp in 2010, all of which were declined?

WhatsApp for Android had only launched in August 2010, after Symbian in May and BlackBerry earlier that year.

Which venture firm, via partner Jim Goetz, bought over 15% of WhatsApp in April 2011?

Partner Jim Goetz negotiated for months; the firm eventually earned an approximate 5,000% return when Facebook bought the company.

On February 19, 2014, Mark Zuckerberg's company agreed to buy WhatsApp for roughly how much?

It was the largest acquisition of a venture-backed company in history: $4 billion in cash, $12 billion in Facebook shares and $3 billion in restricted stock for the founders.

How many staff did WhatsApp have in February 2013, already one of the world's biggest messaging services?

That same month Sequoia put in another $50 million at a $1.5 billion valuation, a year before Facebook paid more than twelve times that.

Which research app that Facebook used to monitor competitors' usage influenced its decision to buy WhatsApp?

Days after the deal was announced, WhatsApp suffered an outage, and rivals Telegram and Line claimed millions of new sign-ups.

How much was the annual subscription fee that WhatsApp announced it was dropping in January 2016?

Koum said the fee was a barrier for users without payment cards, and promised the app would not show third-party ads.

In May 2017 the European Commission fined WhatsApp's parent for misleading takeover information. How much?

Facebook had claimed in 2014 that automatically combining WhatsApp and Facebook user data was technically impossible, then began doing exactly that in 2016.

Brian Acton left WhatsApp in September 2017 to fund a nonprofit behind which rival messaging app?

The Signal Foundation's app uses the same encryption protocol WhatsApp had adopted; Acton explained his exit in a Forbes interview a year later.

Who was named as Jan Koum's replacement after he announced his departure as WhatsApp CEO in April 2018?

Koum was thought to have walked away from about $1 billion in unvested stock, but reportedly kept $450 million through a 'rest and vest' arrangement.

How many monthly active users did WhatsApp report reaching in May 2025?

It had passed one billion in February 2016 and two billion in February 2020, and by 2025 was the most popular messenger app in the world.

WhatsApp's end-to-end encryption uses a protocol developed by which organisation?

The partnership was announced on November 18, 2014, and the rollout was declared complete for 'every form of communication' on April 5, 2016.

WhatsApp is built on a customised version of which open messaging standard?

A 2019 court document from the NSO Group case named the variant 'FunXMPP'; each account's username is the phone number followed by @s.whatsapp.net.

What do users scan with their phone to log in to WhatsApp Web, which launched in January 2015?

At launch the phone had to stay online for the browser session to work; that requirement disappeared with multi-device support in 2021-23.

In which year did WhatsApp add voice calls between two accounts?

By June 2016 the company said more than 100 million voice calls a day were being placed; video calls between two accounts arrived in November 2016.

Which audio codec does WhatsApp use for its voice calls?

It runs at 8-16 kHz sampling rates and relies on MDCT and linear predictive coding compression.

WhatsApp's Status feature, launched in 2017, copied which rival apps' stories format?

It later gained Voice Status Updates, letting people share voice notes as their status.

When WhatsApp let users edit sent messages in May 2023, how long was the editing window?

Edited messages are tagged 'edited', and text formatting like code blocks and bulleted lists arrived at the same time.

In May 2022, WhatsApp raised its file upload limit from 100 MB to what?

The same update lifted the maximum group size to 512 members; all-file-type uploads had only been allowed since July 2017.

What is the maximum number of participants in a WhatsApp video call after the June 2024 improvements?

The same update added audio to screen sharing and a new codec for reliability; groups larger than 32 can use the separate 'voice chat' feature instead.

How long can a WhatsApp video message, introduced in July 2023, last?

Like voice messages, they are recorded straight into the chat without saving anything to the phone's gallery.

WhatsApp Channels launched in June 2023 in just two countries first. Which two?

Unlike chats and groups, channel broadcasts are not end-to-end encrypted; the feature went global in September 2023.

Which three countries first got WhatsApp's third-party animated stickers in March 2021?

Sticker support itself dates from October 2018, and unusually WhatsApp requires third-party apps to add sticker packs.

On November 30, 2015, WhatsApp's Android app made links to which rival service unclickable?

Multiple sources confirmed it was intentional rather than a bug, and WhatsApp offered no explanation for what critics called an anti-competitive move.

Which Israeli surveillance firm did WhatsApp sue in 2019 over spyware injected via voice calls?

The Pegasus exploit could infect a phone through a call the target never answered, and hit at least 1,400 users in 20 countries.

On which 2016 date did WhatsApp announce end-to-end encryption for all communication on the app?

A German magazine had shown a year earlier that Android-to-Android messages were encrypted but iPhone messages were not yet.

WhatsApp Pay became generally available for peer-to-peer transfers in which two countries?

In India it runs on the UPI system and was capped at 20 million users in 2020 before opening to everyone in August 2022; Brazil's central bank briefly ordered Visa and Mastercard to stop working with it in 2020.

Which country is by far WhatsApp's largest market by number of users?

It passed 200 million monthly users there in February 2017, and WhatsApp added forwarded-message labels after misinformation there led to lynchings.

In September 2017, security researchers reported WhatsApp completely blocked in which country?

Apple later removed the app from its App Store there in April 2024, citing government orders on national security grounds.

In May 2016, a court order forced mobile providers in which country to block WhatsApp for 72 hours?

It was the second time the service was punished for failing to cooperate with criminal court orders, and the block was lifted on appeal within a day.

Which country's army banned WhatsApp in December 2021, telling personnel to use the home-grown Threema instead?

The concern was that U.S. authorities could reach WhatsApp data through the CLOUD Act.

Which country briefly banned WhatsApp in 2016 after the Russian ambassador was assassinated there?

The UAE, by contrast, has blocked WhatsApp voice and video calls since about 2013 to protect its state-owned telecoms.

Which two organisations did WhatsApp partner with in March 2020 to run COVID-19 information hotlines?

That same month it began testing tools to help users check the context of forwarded information.

In which region did WhatsApp's January 2021 privacy-policy update not apply, because it breached GDPR?

WhatsApp postponed the update to May 15, 2021, and said it would not cut off users who declined the new terms.

Which EU law forced Meta in March 2024 to let third-party apps interoperate with WhatsApp?

Messages sent between other apps and WhatsApp are meant to keep end-to-end encryption.

How many messages a day was WhatsApp handling in August 2012?

The Financial Times said WhatsApp had done to SMS what Skype did to international calling on landlines.

WhatsApp was ranked in which position among the most downloaded mobile apps of the decade 2010-2019?

The same December 2019 announcement said the app would stop supporting Windows Phone at the end of the year.

In which city was WhatsApp co-founder Jan Koum born?

He moved with his mother and grandmother to Mountain View, California, at 16, and worked as a grocery-store cleaner while she babysat.

Which company rejected both Jan Koum and Brian Acton when they applied after leaving Yahoo?

They had spent a year off travelling around South America and playing ultimate frisbee before applying.

Which two future Napster creators did Jan Koum meet through the computer security think tank w00w00?

Koum was working as a security tester at Ernst & Young while enrolled at San Jose State, before dropping out to join Yahoo in 1997.

On which date did WhatsApp become officially supported on the iPad?

Like the web, Windows and Mac versions, the iPad app is a linked device that syncs with WhatsApp on a phone.

Where did Koum's friend find Igor Solomennikov, the developer who built the first iPhone version?

Alex Fishman found him on the freelance site; the earliest users were a handful of Fishman's friends in San Jose.

When WhatsApp raised its file limit to 2 GB in May 2022, the maximum group size grew to how many members?

The previous cap had stood since the era when group chats were limited to a few hundred people.

Whose phone was hacked via a malicious WhatsApp file sent from the Saudi crown prince's account?

UN special rapporteurs later confirmed the hack, linking it to the targeting of people close to journalist Jamal Khashoggi.

When WhatsApp first let users delete messages sent by mistake in November 2017, how long was the window?

Video calling had arrived a year earlier, in November 2016, for Android, iPhone and Windows Phone users.

Which country fully blocked WhatsApp in February 2026, despite it having at least 100 million users there?

The government cited alleged failures to comply with domestic rules on extremist content and state oversight.