The chat app three billion people can't easily leave.
Benchmark review. Giants are reviewed rarely, to show what the tools in the directory are measured against. This one is not listed in the directory or the leaderboard, and it is an example, not a recommendation.
Image from www.whatsapp.com, taken 2026-10-23. The images belong to their makers and are shown to help you recognise the tool. Ask us to remove one.
WhatsApp is how about three billion people keep in touch, and that scale is both its strength and its trap. Messages are end-to-end encrypted with the Signal protocol, which is a real protection, but you need a phone number to join, the app is run by Meta, and what Meta can see about who talks to whom is a long-running worry. Backups are encrypted only if you switch that on, and Meta's AI assistant now sits inside the app.
Leaving costs you your whole circle, because taking your conversations with you is hard and the company has pursued unofficial clients in the past. In the EU the Digital Markets Act requires it to let other services connect, which could loosen the grip. For nearly everyone it simply works, so Delivery is its one top score.