Three days after announcing the Facebook purchase, Koum said they were working to introduce voice calls. Although Acton was working on another startup idea, he decided to join the company. Koum then hired a friend in Los Angeles, Chris Peiffer, to develop a BlackBerry version, which arrived two months later. However, when early versions of WhatsApp kept crashing, Koum considered giving up and looking for a new job. A month earlier, after Koum purchased an iPhone, he and Acton decided to create an app for the App Store. The idea Tuuri Kasino started off as an app that would display statuses in a phone’s Contacts menu, showing if a person was at work or on a call.

Version 25.33.73

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• The service was created by WhatsApp Inc. of Mountain View, California, which was acquired by Facebook in February 2014 for approximately US$19.3 billion.

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• In July 2017, WhatsApp added support for file uploads of all file types, with a limit of 100 MB.
• As of 2025, the software requires at least Android version 5.0 or iOS version 15.1 respectively.

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• In April 2023, the app rolled out a feature that would allow account access across multiple phones, in a shift that would make it more like competitors.

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• The web client was not standalone, and required the user’s phone to stay on and connected to the internet.

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• The organization reported a massive drop-off in traffic for the blocked services, though the country’s government made no official statements about the block.

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Linked devices automatically log out after 14 days of inactivity on the primary phone. In June 2023, a feature called WhatsApp Channels was launched which allows content creators, public figures and organizations to send newsletter-like broadcasts to large numbers of users. Unlike messages in groups or private chats, channels are not end-to-end encrypted. In October 2023 they also introduced passkey support, where a user can verify their login with on-device biometrics, rather than SMS. In November 2023, WhatsApp also began rolling out support for sending login codes to a linked email address, rather than via SMS. Voice calls between two accounts were added to the app in March and April 2015.

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• The company also announced plans to implement reactions, the ability for administrators to delete messages in groups and voice calls up to 32 participants.

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• Linked devices automatically log out after 14 days of inactivity on the primary phone.

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• In September 2017, security researchers reported to The New York Times that the WhatsApp service had been completely blocked in China.

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• In November 2020, UPI payments via WhatsApp were initially restricted to 20 million users, and to 100 million users in April 2022, and became generally available to everyone in August 2022.

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• WhatsApp has been officially supported for iPads and its iPadOS since May 27, 2025.
• Sequoia Capital received an approximate 5,000% return on its initial investment.

WhatsApp Messenger

• In January 2018, WhatsApp released a standalone business app called WhatsApp Business which can communicate with the standard WhatsApp client.
• The idea started off as an app that would display statuses in a phone’s Contacts menu, showing if a person was at work or on a call.

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• Now, the feature is also made available to iOS users, allowing them to link up to four iPhones.

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• The Cloud API enables businesses to integrate WhatsApp with other software, have a central WhatsApp account for multiple users and implement advanced automation.

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• The desktop version was first only available to Android, BlackBerry, and Windows Phone users.

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• Voice calls between two accounts were added to the app in March and April 2015.

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This was implemented only on Samsung phones, with plans to expand to Android and iOS “soon”. In July 2017, WhatsApp added support for file uploads of all file types, with a limit of 100 MB. In November 2023, WhatsApp added a “voice chat” feature for groups with more than 32 members. In 2022, WhatsApp added the ability for users to turn off their online status.

Status Saver Video Photo Save

Koum updated WhatsApp so that everyone in the user’s network would be notified when a user’s status changed. On June 13, 2013, WhatsApp announced that they had reached their new daily record by processing 27 billion messages. According to the Financial Times, WhatsApp “has done to SMS on mobile phones what Skype did to international calling on landlines”.

imo-International Calls & Chat

At that point WhatsApp was adding about 25 million new users every month, or 833,000 active users per day. The organization reported a massive drop-off in traffic for the blocked services, though the country’s government made no official statements about the block. In May 2019, WhatsApp was attacked by hackers who installed spyware on a number of victims’ smartphones. A Wired report noted the attack was able to inject malware via calls to the targeted phone, even if the user did not answer the call. In January 2022, an unsealed surveillance application revealed that WhatsApp started tracking seven users from China and Macau in November 2021, based on a request from US DEA investigators. The app collected data on who the users contacted and how often, and when and how they were using the app.

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On November 14, 2016, WhatsApp added video calling for users using Android, iPhone, and Windows Phone devices. This ability (named multi-device support) began testing in July 2021 and rolled out to all users in April 2023. They link to and sync with WhatsApp actively running on a supported primary phone.