Messaging apps: We're using them more often, to perform a broadening variety of tasks -- sharing photos and documents, ordering food, making payments, summoning chatbots for help. For many users, messaging is already preferable to email and phone calls. But the more you do with your messaging apps, and the more personal information you entrust to them, the more protection they should offer.
The truth is, not all messengers are secure messaging apps. They differ greatly in their privacy policies, app permissions, and levels of encryption. Some are simply more locked down, offering end-to-end encryption, the ability to conceal yourself and your activities, or the option to delete your messages altogether. We've evaluated the big-name messengers you may already be using, as well as smaller but more security-savvy players, to pick the messaging apps that offer you the most privacy and security.
The big-name messengers
You're on certain messaging apps because that's where your friends are, you know how to use the features, and you probably don't want to switch. But if you're privacy-minded, the following popular messengers have become much more security conscious in recent years, and they should have levels of protection that are fine for most users. (If you want more heavy-duty security, skip ahead to the next section.)
To start using WhatsApp, you must provide a name, a phone number, and access to your contacts. WhatsApp recently introduced end-to-end encryption for texts and calls, which makes it one of the safer options today. But please note: You and your contact must both be using the latest version of WhatsApp for end-to-end encryption to be activated. Once a message is delivered -- or after 30 days of it being undelivered -- WhatsApp erases the message.
By default, anyone who has your number can see your Last Seen, your profile photo, and your status. If you don't want your contacts to see that info, go to Settings, Account, then Privacy and change the setting to Nobody. Changing Last Seen to Nobody means you won't be able to see other peoples' Last Seen either.
When you register with Viber, you only have to provide a phone number and access to your address book. Only users with your number or in your groups will see this info. As in WhatsApp, in Viber you can go to Settings, then Privacy, to make sure that your connection status and the last time you were online don't appear.
Viber also uses end-to-end encryption. The Hidden Chats feature enables you to conceal individual or group messages from your chat history unless you enter a PIN. To hide a chat on iOS, swipe left and tap the hide button. On Android, long-hold the chat and tap the hide button. Viber will ask you to set a four-digit PIN. iOS users can use Touch ID instead of a PIN. To view hidden chats, scroll down to display Search and type your four-digit code. Viber has also recently introduced a feature -- Delete for Everyone -- that enables you to delete chats from your and your recipients' devices.
With Line, you can register with a phone number, an email address, or a Facebook account. Like WhatsApp and Viber, Line offers end-to-end encryption of your messages via Letter Sealing, found under Settings, then Chat & Voice Calls. Line also has hidden chats with time-limiting messages that you can set to expire between one minute and one week, as well as protection in the form of a four-digit passcode that you must enter after your phone times out.
If you've registered with your phone number, then others who have your phone number can use it to find you. You can disable the Allow Others to Add feature under Settings and then Friends.
If you ever wish to delete message exchanges, go to Settings, Chats & Voice Calls, then Clear Chat History. You can also Delete Files From Chats in the same place. Line promises that its True Delete function makes erased data irrecoverable.
Facebook's Messenger app really upped its security game with the introduction of Secret Conversations. Send messages, pictures, and stickers, confident that your interaction is encrypted end to end. For extra protection, you can set a timer to erase extra sensitive messages from the conversation. Unfortunately you cannot yet send group messages, GIFs, videos, or payments via Secret Conversations, nor can you make voice or video calls.
More secure messaging apps
Want more security than the typical messaging app offers? These apps were built with privacy in mind, by developers with years of security experience, and they give you additional settings and options to lock down your conversations or go completely incognito.
Sign up with your telephone number and enjoy end-to-end encrypted chat on Secret Chats; otherwise Telegram's messages are AES-256 encrypted. Secret Chat messages -- which can include text, photos, videos, and files -- are sent over an encrypted connection, automatically self-destruct after receipt, and cannot be forwarded.
Under Settings, then Privacy and Security, you can set your Last Seen to Nobody for maximum privacy. Other options include setting a Passcode Lock for when the app times out, and enabling Two-Step Verification, which will be required each time you log on from a new device.
The cherry on top: Telegram promises to never give third parties access to your data.
BitTorrent Bleep doesn't force you to create an account. The app asks you to pick a nickname and to offer up your contacts, but it doesn't force you to do the latter -- so you can go incognito. But if you want to help friends find you, then you need to provide your email or phone number. Once you're in, start sending private messages called Whispers. These messages are end-to-end encrypted, time-limited, and are never stored anywhere -- in a cloud or on your phone -- and that includes any identifying metadata.
Add a user ID and number (contacts are optional) to begin using Wickr Me. The app promises that all your communications -- audio, video, voice, and text -- are end-to-end encrypted and no metadata is kept. When you delete a message, or when the time limit you set expires, the Secure Shredder makes sure that the message is irrecoverable. You can enable an app password after periods of inactivity lasting from five seconds to a day. One unusual security setting: If you want to use Wickr Me's unique Audio playback option, you must use a headset.
Dust asks you to sign up with your email or social media account.You can send end-to-end encrypted messages -- text, links, stickers, photos, videos, etcetera -- to individuals, but Dust is unique in also letting you message to groups or send blasts to your followers. Messages and blasts disappear as soon as they're read or within a day, and all data is erased. If your recipient takes a screenshot, Dust will notify you. Better yet, your name isn't used in chats, so a screenshot can't reveal your identity.
After you verifying your phone number and share your contacts, Signal enables you to communicate by phone or text with existing contacts who are on the app. Communications are encrypted end to end, and no data is saved. To ensure that no one takes screenshots of your messages, go to Settings, Privacy, then Enable Screen Security. There you can also tap Clear History Logs every once in awhile to delete your message, attachment, and call history. The app's source code is available at GitHub for independent verification.
Billing itself as a "modern" private messenger, Wire's interface looks fun, almost whimsical. The app enables you to communicate via photos, sketches, GIFs, and phone and video calls, and you can be confident that communications are encrypted end to end. You can also send files of up to 25MB anonymously, from your cloud services. Wire also enables group chat for up to 128 people.