What we found
WhatsApp: DYour phone number is your WhatsApp identity, visible to everyone you chat with.
Phone number required and permanently visible in all chats. Links identity to real name via SIM registration laws. Contact discovery loophole exploited by Vienna researchers to harvest metadata on 3.5B account identifiers (2025).
Facebook Messenger: DMeta told Congress that Messenger messages are private.
In 2022, Meta provided a 17-year-old's abortion-related DMs to Nebraska police from plaintext storage, enabling felony charges. Meta complied with 76% of 476,802 government data requests globally (88% US).
WeChat: DWeChat Pay processes $16 trillion a year in transactions, every one tied to a government ID.
WeChat Pay processes over $16 trillion annually, all linked to real-name verified government IDs. Leaked documents from the Urumqi Public Security Bureau showed officers using WeChat Pay records to track Uyghur diaspora members' financial connections, mapping family networks through money transfers.
Discord: DDiscord says it takes child safety seriously.
The National Center on Sexual Exploitation placed Discord on its Dirty Dozen list four consecutive years. New Jersey AG Matthew Platkin sued in April 2025 alleging default settings exposed children to sexual exploitation. Multiple state lawsuits document adults grooming minors. Discord's design — open servers, DM-by-default, minimal age gates — creates what prosecutors call grooming-friendly architecture.
Telegram: DTelegram says your messages are 'heavily encrypted' but actually holds the keys to read almost all of them.
Default Cloud Chats use only client-server encryption. Telegram holds the decryption keys. Only opt-in Secret Chats are E2E — buried in UI, device-bound, no desktop, no groups. With 950M+ MAU, essentially all conversations are server-readable.
Slack: DSlack calls your DMs "private." Your employer can export every private message, every deleted message, every file you ever shared — without telling you.
Compliance Export on Business+ and Enterprise Grid allows administrators to export every message — including DMs, private channels, and deleted messages — without notifying employees. Your boss can read every private message, every deleted rant, every DM about job hunting.