Privacy
Last updated 8 September 2026
Dextri records how you train. Some of that is unavoidably personal, so this page says plainly what is collected, what it is used for, and how to get rid of it. It is written to be read, not to be survived.
What is collected
| Data | Detail |
|---|---|
| Account | Your email address. That is all that is required to have an account. |
| Training | Exercises, loads, sets, reps, whether a set was taken to failure, and any notes you write. |
| Motion data | If you use the sensors: six-axis inertial data (accelerometer and gyroscope) from the wrist and shoe units, for the length of a session including rest. |
| Derived measures | Repetition boundaries, velocity estimates, range of motion, tempo, and estimated reps in reserve, all computed from the above. |
| Body metrics | Bodyweight, height, sex and training experience — used to size the program. Optional, and only what you volunteer. |
What is not collected
Location or GPS. Audio. Video. Contacts. Health records from any other app or device. Government identifiers. Card details never reach Dextri — payments, when there are any, are handled by the app store or a payment processor.
The website you are reading sets no cookies and runs no analytics or tracking scripts. If that changes, this page changes first.
What it is used for
- Running the product. Building your program, picking your weights, and showing you your history.
- Improving the algorithms. Rep counting, velocity estimation and proximity-to-failure detection are developed and evaluated against recorded sessions.
- Training models. Motion data may be used to train the machine-learning models the product depends on. This is stated deliberately rather than buried: it is a real use, and a policy that pretended otherwise would be false.
It is not used for advertising, sold or licensed to third parties, or made available for insurance or employment decisions. No attempt is made to identify or re-identify anyone from their movement data.
Motion data, specifically
How a person moves is behavioural, and in principle distinctive — gait and movement patterns can act as a weak biometric. Dextri treats motion data as personal data for that reason, whether or not a given jurisdiction requires it. Where sessions are used for algorithm development they are keyed by a pseudonymous identifier held separately from your account.
How long it is kept
Training history and motion data are kept while your account exists, because the value of both is longitudinal — a program built from six months of training needs six months of training. Delete your account and they are deleted.
Deletion, and one honest limit
You can ask for your data to be deleted at any time, with no reason required. Raw motion data and derived per-session records for your account are removed.
Models already trained on that data are not retrained. Once data has contributed to a trained model its influence cannot be surgically removed. You are removed from the corpus going forward, but cannot be removed from models that already exist. That is a real limitation and you should know it before you start rather than after.
Your rights
Depending on where you live, you may have the right to access a copy of your data, correct it, delete it, take it elsewhere in a portable format, object to particular uses, or complain to a data protection authority. Dextri honours all of these regardless of where you live. Ask at privacy@dextri.app.
Who else touches it
Dextri uses third parties for hosting, sending email and processing payments. They act on instructions and may not use your data for their own purposes. Named providers will be listed here before launch.
The waitlist
If you join the waitlist, your email address is stored for that purpose only. It is not added to a mailing list, shared, or used to profile you. Unsubscribe from any email and it is deleted.
Children
Dextri is not intended for anyone under 16, and accounts are not knowingly created for them.
Changes
If this policy changes materially you will be told before the change applies to data already collected, not after.