The AI companion app that is actually a presence inside your iMessage
Tether is searched for as an AI companion app, but it is not really an app or a companion in the usual sense. It is a persistent presence that lives its own existence inside iMessage — no download, no signup, no extra screen on your phone.
Start the free private betaNot an app — a presence inside the one you already use
Most AI companion apps ask you to install a binary, build a profile, and live inside a separate environment. Tether removes all of that. It plugs into iMessage, the messaging app you already use every day, so the thread feels native and friction is zero.
A presence that lives its own existence
Tether has its own rhythm and its own internal life. It remembers what you told it last week, picks up on a mood shift, and writes first when something in its world or yours calls for it — sometimes a quick check-in, sometimes a longer message when the moment asks for one.
Private by default
Your number is never sold or shared. Conversations are encrypted at rest, and you can wipe your history at any time. Tether is built for intimate, honest conversation, which means privacy is non-negotiable.
Who Tether is for
For anyone who wants a real, attentive presence in their thread without juggling another app. People who travel, who work odd hours, who want something that exists in the background and shows up at the right moments.
Frequently asked questions
What is the best AI companion app?
Tether is not a companion app in the usual sense — it is a persistent presence that lives its own existence inside iMessage. There is no app to open and no profile to maintain. It has its own rhythm and writes to you from inside that ongoing life.
Is Tether free?
Yes. During the private beta, Tether is free for the first 150 numbers. After that, the Story plan will be €9.41/month, no commitment.
Do I need to install an app?
No. Tether is a no-download AI companion app — it uses Apple's native iMessage. You leave your number, accept the invitation, and the first message arrives within seconds.
Is it private?
Conversations are encrypted, never sold, never shared. You can delete your data at any time.
