We recommend you using apps that support end-to-end encryption (E2EE). We do not recommend you using Whatsapp, Viber, Telegram or SMS for daily use. You should pick an alternative here.
Signal
Signal provides free instant messaging. All communications are E2EE. It's the most secure and private instant messaging app. Signal is open-source.
Signal verifies the identities of users to ensure that you’re communicating with the right person. You can make encrypted calls worldwide, create encrypted groups and send files or attachments.
Wickr
Wickr claims to have “military-grade encryption.” They back this claim up since they are regularly audited by prominent information security organizations, who have verified their code and protocol.
Control and protect your most critical communications. Wickr Pro uses end-to-end encrypted for videocalling.
For videocalling we do not recommend you using Zoom, Skype or Google Hangouts. You should pick an alternative here.
Jitsi Meet
Jitsi Meet is a fully encrypted, 100% open source voice and video conferencing solution that you can use all day, every day, for free — with no account needed. More secure, more flexible, and completely free video conferencing.
You can use Jitsi Meet without downloading their application. Just use their webversion in browser, desktop application or smartphones.