The founders of Truth created this anonymous messaging app so people would be able to send private messages to people on their contact lists. It is basically incognito one-on-one messaging between contacts. When you send a truth message, you are assigned to an anonymous username and avatar so no one knows who you are.
If the person you are messaging already has the app it will show up in the app's email. If they do not already have the app downloaded they will receive a text message displaying only part of the truth message and it will prompt the recipient to download the app the see the rest.
Truth cofounder Ali Saheli told Mashable that, "You shout out anonymously, kind of like on Twitter. The concept of [messaging] phone contacts was more interesting to us."