WhatsApp Inc., was founded in 2009 by Brian Acton and Jan Koum, both former employees of Yahoo!. After Koum and Acton left Yahoo! in September 2007, the duo travelled to South America as a break from work. At one point they applied for jobs at Facebook but were rejected. For the rest of the following years Koum relied on his $400,000 savings from Yahoo!. In January 2009, after purchasing an iPhone and realizing that the seven-month-old App Store was about to spawn a whole new industry of apps, he started visiting his friend Alex Fishman in West San Jose where the three would discuss "...having statuses next to individual names of the people," but this was not possible without an iPhone developer, so Fishman introduced Koum to Igor Solomennikov, a developer in Russia that he had found on RentACoder.com. Koum almost immediately chose the name "WhatsApp" because it sounded like "what's up", and a week later on his birthday, on February 24, 2009, he incorporated WhatsApp Inc. in California. However, early WhatsApp kept crashing or getting stuck and at a particular point, Koum felt like giving up and looking for a new job, upon which Acton encouraged him to wait for a "few more months".

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