More than 1 billion people use WhatsApp. The founders of WhatsApp created the app placing privacy first. Facebook bought WhatsApp, and started changing privacy related factors in order to push advertisements. As a natural result, huge amount of personal data is being harvested. Even WhatsApp founders took issues with it and left Facebook prematurely.
Signal is an alternative to WhatsApp, and built as robustly as WhatsApp and collects very minimal data so as to make messaging work. Brian, one of the WhatsApp founder, also injected $50million of his personal money to support Signal. https://www.wired.com/story/signal-foundation-whatsapp-brian-acton/
A quick comparison of all the data WhatsApp, Facebook messenger, Signal and Telegram. Take a look and make an informed choice.
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