In June 2009, Apple propelled push notices, giving designers a chance to ping clients when they were not utilizing an application. Koum overhauled WhatsApp so every time the client changed their statuses, it would ping everybody in the client's network.WhatsApp 2.0 was discharged with an informing part and the dynamic clients all of a sudden swelled to 250,000. Koum went by Acton, who was still unemployed while overseeing another unsuccessful startup and chose to join the organization. In October Acton influenced five ex-Yahoo! companions to put $250,000 in seed financing, and subsequently was allowed fellow benefactor status and a stake. He formally joined on November 1. After months at beta stage, the application in the long run propelled in November 2009 solely on the App Store for the iPhone. Koum then procured an old companion who lived in Los Angeles, Chris Peiffer, to make the BlackBerry rendition, which arrived two months after the fact.
WhatsApp was changed from an allowed to paid support of abstain from developing too quick, mostly on the grounds that the essential expense was sending check writings to clients. In December 2009 WhatsApp for the iPhone was upgraded to send photographs. By mid 2011, WhatsApp was in the main 20 of all applications in Apple's U.S. Application Store.
In April 2011, the organizers consented to take $7 million from Sequoia Capital on top of their $250,000 seed subsidizing, following quite a while of arrangement with Sequoia accomplice Jim Goetz.According to Goetz, the investment firm initially found WhatsApp through an App store following framework they created called 'prompt riser', during an era when the application was considerably more prominent in different nations than in the US. Notwithstanding, it took months for the VC firm to find Koum and Acton, given that the organization didn't have an openly accessible location nor signage at the time. All Goetz knew was that they were situated in Mountain View, and Sequoia accomplices "truly strolled the lanes of Mountain View to check whether [they] could meet with [Koum and Acton]."
By February 2013, WhatsApp's client base had swollen to around 200 million dynamic clients and its staff to 50. Sequoia contributed another $50 million, esteeming WhatsApp at $1.5 billion.