DrJekyll
Last updated: October 24, 2026
DrJekyll is a personal lab result monitoring app for cancer patients. It reads lab results from Apple Health on your iPhone, displays them as trend charts over time, and helps you prepare better questions for your care team. The app is published by DRJEKYLLAPPS LLC, a New York limited liability company ("we" or "us"). Earlier versions were called "Dr. Jekyll," and you may still see that name in the app while we complete the change.
DrJekyll connects the dots between the lab data already in your Apple Health records and a clearer picture of your trends over time. It does not diagnose anything, does not give medical advice, and does not generate clinical recommendations of its own.
DrJekyll is an organizational tool, not a medical one. Nothing displayed in the app, and nothing generated through the optional Ask Claude feature described below, is medical advice, a diagnosis, or a treatment recommendation.
Lab data shown in the app reflects whatever has synced to Apple Health from your providers' records, and may be incomplete, delayed, or affected by sync errors. Reference ranges shown are either the ranges your lab supplied with the result or general defaults, and may differ from the ranges your doctor uses. Always talk to your oncologist or care team about what your results mean and before making any decision based on anything you see in this app.
Through the app: nothing. DrJekyll has no backend server, database, account system, analytics, crash-reporting service, or advertising. No company server touches your health data.
The only information the app stores on your device is your preferences: which lab tests you have chosen to monitor and your date range settings. These are stored locally using Apple's SwiftData framework and stay on your device.
Outside the app, limited information may reach us in these ways:
We do not sell your personal information and do not share it for advertising.
DrJekyll reads lab results from Apple Health using Apple's HealthKit framework. This requires your explicit permission, which you grant through Apple's standard health authorization prompt.
You can revoke DrJekyll's access to Apple Health at any time:
Settings → Privacy & Security → Health → DrJekyllDrJekyll includes a feature that helps you build a prompt to bring into a conversation with Claude, a separate AI product made by Anthropic, PBC. Before you can use it, the app shows a consent screen explaining what information will be included and who receives it. This feature:
DrJekyll itself never sends any data to Claude or Anthropic. The prompt leaves your device only when you paste and send it in the Claude app, and from that point Anthropic's privacy practices apply, not ours. We cannot see, retrieve, or delete what you share with Claude. Anthropic's privacy policy is at anthropic.com/legal/privacy.
Any response you receive from Claude, including trend analysis, plain-language explanations, or suggested questions for your doctor, is generated by Anthropic's product. We do not review or curate it, and it is not medical advice.
You can turn this feature off at any time in Health Connection settings.
DrJekyll uses Face ID (or your device passcode as a fallback) to prevent others from viewing your health data if they pick up your phone. Face ID is handled entirely by Apple's LocalAuthentication framework. DrJekyll never sees or stores your biometric data.
Because your lab results stay on your device, their protection depends mainly on your device settings. Use a passcode, keep your iPhone updated, and be careful about who has access to your unlocked phone and your Apple Health data. No system is perfectly secure, and we cannot guarantee absolute security.
DrJekyll includes a Demo Mode that displays sample lab data for a fictional Multiple Myeloma patient. Demo Mode does not use or display any of your real health data.
If you are using DrJekyll through Apple TestFlight, you are using pre-release software that may contain bugs or incomplete features. Use during this period is at your own risk, and the app should not be relied on as your sole source of health information.
DrJekyll may be used outside the United States. Because the app has no backend and does not transmit your health data to us, most data protection obligations that apply to companies storing data on servers do not arise the same way here. If you use the optional Ask Claude feature, your data is subject to Anthropic's own privacy practices at that point, regardless of where you are located.
DrJekyll is not directed at children under 13 and does not knowingly collect information from children.
If this policy changes materially, we will update the date at the top of this page. Because the app itself collects no data, we expect changes to be minimal.
DrJekyll is published by DRJEKYLLAPPS LLC, New York, NY.
Questions about this privacy policy: privacy@drjekyllapps.com