Effective November 5, 2026

Privacy Policy

Lentra keeps your data on your iPhone. We don't run a server for the app, we don't have accounts, and we can't see your weight, your photos or your health data. There are no ads, no analytics and no tracking.

This policy covers the Lentra iPhone app and the lentra.app website. Both are run by Paul Winchell, doing business as Lentra, while Lentra LLC (a Hawaii limited liability company) completes formation ("we", "us"). Once it does, the LLC takes over the app and this policy. If anything here is unclear, write to [email protected].

The short version

• Everything you enter in the app stays on your phone.
• Your progress photos are encrypted inside the app and are never added to your photo library unless you export one.
• We never sell or share your data, and we never use it for advertising.
• You can export everything or delete everything at any time.
• The only data we hold is the email address you give us if you join the waitlist on this website.

What the app stores, and where

The app stores the following on your iPhone, inside the app's own storage:

• Weights, body measurements (such as waist), goals and your trend settings.
• Medication markers you choose to log: the medication name, dose and date. Lentra only shows these on your chart and report. It doesn't estimate doses or give medical advice.
• Notes and non-scale wins you log.
• Progress photos. Each photo is encrypted with AES-256 using a key kept in your iPhone's Keychain.
• The start date of your free trial, kept in the Keychain.

None of this is sent to us or to anyone else. We have no server that could receive it.

Apple Health

If you connect Apple Health, Lentra reads your weight, body fat, lean body mass, waist and height so your history appears on the trend chart. It saves the weights and waist measurements you type in to Apple Health. It never writes estimated values.

Data from Apple Health is used only to show you your own progress inside the app. It is never used for advertising, never sold, never shared with third parties and never stored by us. You can change Lentra's access at any time in the Health app: tap your profile picture, then Apps > Lentra.

Camera, photos and Face ID

• Camera: used only to take progress photos inside the app. Alignment runs on your phone.
• Photo library: Lentra saves a photo, comparison or timelapse to your library only when you tap export.
• Face ID: optional, to lock your photos or the whole app. Face ID is handled by iOS. Lentra never receives your face data.

Doctor reports, exports and backups

The doctor report is a PDF made on your phone. CSV exports and backup files are made on your phone too. They go only where you send them, for example to your doctor by email, to the Files app or to AirDrop. Once you share a file, the app you share it with handles it under its own privacy terms.

Backup files are encrypted with a password you choose (AES-256). We don't have that password and can't recover it for you.

Your normal iPhone backup (to iCloud or a computer) includes Lentra's data. Photos stay encrypted in that backup. Lentra does not sync with iCloud or any other cloud service on its own.

Purchases

Subscriptions and the one-time purchase go through Apple's App Store. Apple handles the payment. We never see your card or your Apple ID. The app checks with Apple only to confirm what you've bought.

The waitlist on this website

If you join the waitlist, we store your email address and the date you joined. We use it to send one email when Lentra is available, and for nothing else. It is stored with Cloudflare, which hosts this site. It is never sold or shared.

The waitlist also asks whether you take a GLP-1 medication. That answer is optional. It is added to an anonymous count and is never stored with your email address.

To be removed from the waitlist, email [email protected] and we will delete your address.

This site uses no cookies, analytics or ad trackers. Like any website host, Cloudflare processes basic connection data such as IP addresses to deliver and protect the site. The site loads two typefaces from Google Fonts, so your browser connects to Google when the page loads.

Deleting your data

In the app, go to Settings and tap Delete everything. You can also delete the app. Either way, everything Lentra stored on your phone is removed. Weights already saved to Apple Health stay there, and you can delete them in the Health app.

Children

Lentra is meant for adults and is not directed to children under 13. We do not knowingly collect information from children.

Not medical advice

Lentra is a tracking tool, not a medical device. It doesn't give medical advice. Talk to your doctor or prescriber about your weight, your medication and your goals.

Changes

If this policy changes, we'll post the new version here with a new effective date. If a change affects how the app handles your data, we'll also say so in the app's release notes.

Contact

Paul Winchell, dba Lentra (Lentra LLC, formation pending)
[email protected]