Google Hangouts vs WhatsApp

Google Hangouts
Google Hangouts is a live video chat app. It allows to share your screen, collaboratively draw on a whiteboard, edit Google Docs documents, create broadcasts for the unlimited number of viewers. Splitted into group chat app and videoconferencing app. Secure Google Hangouts alternatives are Signal and Telegram.
WhatsApp Messenger is a cross-platform mobile messaging app which allows you to exchange messages without having to pay for SMS. WhatsApp Messenger is available for iPhone, BlackBerry, Android, Windows Phone and Nokia and yes, those phones can all message each other! Because WhatsApp Messenger uses the same internet data plan that you use for email and web browsing, there is no cost to message and stay in touch with your friends. Secure WhatsApp alternatives are Signal and Telegram.
WhatsApp has better video than Google Hangouts

2016 - WhatsApp now supports full end-to-end encryption. Google Hangouts is in panic

Facebook owned messenger WhatsApp has now fully implemented strong end-to-end encryption on its platform and across all mobile platforms for which it offers apps. End-to-end encryption means the content of communications are not stored in plaintext on WhatsApp’s servers. Nor is the company able to decrypt users’ messages to access them since it does not hold the encryption keys. So WhatsApp will be unable to be compelled to hand over messaging data — even if served with a warrant by authorities demanding access. WhatsApp partnered with Open Whisper Systems and has integrated its widely respected end-to-end encryption Signal Protocol. Although the completion of default end-to-end encryption is a hugely important security milestone for the WhatsApp platform, it does not mean that from here on in every communication sent via the app is end-to-end encrypted, because that’s reliant on all users being upgraded to the latest version of the software.