Wickr vs Pulse SMS

Unlike most, you can use your phone but you don't have to. You can register without giving anything and add contacts either via e-mail (only) or phone number.

Wickr has a feature that not only erases all messages, but also overwrites them with junk data.

Instead of using usernames, emails or phone numbers to find other users, Wickr uses hashes derived from phone numbers or email addresses (this applies to the find friends functionality only). Hashes are the result of a one-way cryptographic function, meaning it's purposefully difficult to reconstruct original data (phone numbers and email addresses in this case) from them. For Wickr, hashes are generated on the client's side so that no personal information is ever sent to the Wickr servers. The app finds people on your contact list that also use Wickr by comparing the hashes that get generated from contacts and comparing them to the hashes that are stored on Wickr servers.

Messages can have a lifespan between 3 seconds and 6 days. Received messages arrive locked. Once they are opened by the recipient, a timer starts counting down until the message is deleted. Of course, the recipient can still copy them or take a screenshot.

Wickr disables the screenshot functionality altogether when the app is open. However, there are ways to circumvent this, as if the user has a rooted phone and has installed apps to overide this block or if a screenshot is taken via some apps that project the screen to a PC.

The editor allows cropping images, drawing and writing text on them as well as add decorations.

It is on GitHub and there's a way to sideload it with Cydia impactor and appsigner.io