互督 vs Cerberus

互督是一款聚焦「熟人监督」的自律打卡与效率提升平台，拒绝独自坚持的孤独，用好友陪伴帮你轻松养成好习惯。 【核心功能】 ▪ 熟人互督：邀请亲友、同学、同事组成监督小组，互相督促打卡 ▪ 自律打卡：支持学习、工作、健身、早起、阅读等全场景习惯打卡 ▪ 实时陪伴：好友状态一目了然，共同坚持，拒绝拖延与摸鱼 ▪ 安全纯粹：仅熟人可见，私密无打扰，专注高效成长 无论你是想提升学习效率、坚持健身计划、改掉拖延习惯，还是需要外部监督驱动行动力，互督都能为你提供最贴合的陪伴式监督体验。 和信任的人一起自律，成长更有动力！

Cerberus is a messenger for conversations that are nobody else's business. Every message, voice note and file is encrypted on your phone and opened only on the phone of the person you are talking to. The server in between carries sealed data and holds no key to any of it — not as a promise not to look, but as a matter of what it has. NO ACCOUNT, NO PHONE NUMBER, NO DIRECTORY There is nothing to sign up for: no email, no SMS, no profile, no password. Nobody can look you up and nobody can add you. A conversation begins when two people are in the same room and one of them scans a code from the other's screen. That is the only way in, and it is the point. WHAT IT PROTECTS • End-to-end encryption with standard cryptography. Keys are generated on the device and stored in the Keychain — they never travel. • The code you show is good once and for a few minutes. The two phones shake hands and move the conversation to a key that was never on any screen, so a code somebody photographed is worth nothing. • A PIN or Face ID on the app itself. • A second PIN for the situation nobody plans for: enter it and the app opens with every conversation hidden, or erases what is on the device, whichever you chose. It shows no error and no sign that another code exists. • Screenshots do not pass silently: the other side is told. • Messages delete themselves on a schedule you set — on both devices and on the server. • A chat list that can show names only, for the moments when your screen is not only yours. AND IT IS STILL A MESSENGER Swipe a message to reply, hold one to react, send photos, videos, files and voice notes, delete anything on your phone or on both phones at once. Everything is where you expect it to be. FREE, AND PRO Two conversations, messages and reactions are free forever — a working messenger, not a trial. Pro adds unlimited conversations, voice notes, photos and files, and deleting on both phones. Take it monthly or yearly with a 3-day free trial, or pay once and keep it for good. Whatever Pro gains later is included at no extra cost. Subscriptions renew automatically until you cancel them in your Apple ID settings. Terms of Use: https://zero-relay.fly.dev/terms WHAT WE CANNOT DO We cannot read your messages, recover them, or reset anything for you. Delete the app and every conversation goes with it: there is no backup, by design, and no way back. To destroy the keys as well, erase from inside the app first — Settings, Security, "Erase everything now". That is the trade this app makes, and it is written here rather than buried in a settings screen.