WhatsApp upgrades Andriod privacy with end-to-end encryption MOUNTAIN VIEW, Calif., Nov. 18 (UPI) -- WhatsApp began switching hundreds of millions of users to a nearly uncrackable encryption system. WhatsApp, considered one of the world's most popular cross-platform messaging apps, partnered with Open WhisperSystems to use the company's TextSecure protocol to incorporate the system for the millions of Android users. It is unclear when the rollout will happen on other platforms, including Apple's iOS. The upgraded encryption, what some are calling the world's most comprehensive data-security system for a messaging service. is said to make messages more secure than ever. WhatsApp messages will now be encrypted from the sender to the recipient, rather than between the user's device and the WhatsApp server. WhatsApp said it will make it almost impossible for anyone to crack the data, including themselves. Privacy experts told the Washington Post the encryption will aid some and handicap others. It will allow WhatsApp's more than 500 million worldwide users to have completely private conversations. But it might also hinder certain investigations, law enforcement said. Earlier this year, FBI Director James B. Comey criticized Apple and Google for developing secure encryption services that are difficult to breach.