WhatsApp, by default, encrypts messages end to end for some other encrypted messenger apps, like Allo, you need to actively choose to chat using end-to-end encryption. Secured end-to-end communications: WhatsApp messages are secured with end-to-end encryption using Open Whisper Systems' Signal Protocol, which is also used in Signal's Private Messenger, Facebook Messenger, and Google Allo. It's free: WhatsApp Web is free to use and doesn't include ads. WhatsApp for PC lets you use the popular messenger app on your Windows PC and chat with WhatsApp-connected family and friends wherever they are. The WhatsApp messaging app isn't just for iPhone and Android phones.
