jack privacy policy

last updated: 10 june 2026

jack is a private, on-device ai assistant. the model runs on your phone, your conversations stay on your phone, and nothing you type or say is ever sent to us or anyone else. this policy explains what that means in practice, in plain terms.

the short version

the only network activity jack itself performs

on-device ai model download (optional). to start chatting you download the model file you select from a public model host (hugging face). this is a normal file download. after that, the model runs entirely on your device and sends nothing over the network when you use it. that is the only network request jack makes on its own.

the one-time pro purchase

jack's optional "pro" unlock is a one-time purchase processed by google play billing. google processes the payment and gives jack an anonymous purchase token; jack never sees your name, email, or payment details. the unlocked state is remembered on your device, and google play restores it automatically on a new device. google's own privacy policy governs the payment itself.

optional hand-offs you explicitly trigger

jack's actions can open another app you already have installed, passing along only what you asked for. these happen only when you (or an action you enabled and confirmed) choose them; jack never does them in the background:

permissions

jack requests only the permissions needed for features you actually use: the microphone for voice input to audio-capable models (recorded on-device, sent to the on-device model, never uploaded), contacts read access only to resolve a name into a number when you ask for a text draft, the internet permission for model downloads, and special access you grant explicitly in android settings (usage access for "about this phone" answers, do-not-disturb access for the quiet-mode action). each is used locally, for the stated feature, and nothing is sent off the device as a result.

the optional accessibility service

jack offers an opt-in accessibility service used for exactly one thing: performing the system "back" navigation action when you ask for it. it is configured so it cannot read your screen and it stays off until you enable it in android's accessibility settings. it is never used for ads, data collection, or anything else.

data deletion

because nothing is stored off your device, there is nothing for us to delete on a server. deleting a chat removes it from your device; removing a model frees its storage. uninstalling jack removes everything.

children

jack is a general-purpose assistant rated for adults and is not directed at children.

changes

if this policy changes, the updated version will be posted at this url with a new "last updated" date.

contact

questions about privacy: keenan@boothcheck.com