JanusMed is designed with privacy as the foundation. By default, you can use the app completely offline — all your health data stays on your device, never touching our servers unless you choose. This guide explains how both modes work, what data flows where, and helps you decide whether creating an account is right for you.
Privacy First: Offline by Default
Unlike most health apps that require you to create an account before you can do anything, JanusMed lets you start using it immediately. No email, no password, no personal information required. When you open the app for the first time, you go straight to setting up what you want to track. All your data is stored locally in your browser using secure IndexedDB storage. This means your sensitive health information never leaves your device unless you explicitly choose to create an account.
How Offline Mode Works
In offline mode, JanusMed stores everything locally on your device: your exam data (extracted biomarkers and values), symptom entries, medications, food logs, lifestyle tracking, health profile, vaccination records, and cycle data. When you upload an exam PDF, it's sent to our servers only for biomarker extraction — this process is completely anonymous with no personal identifiers attached. The extracted data returns to your device and is stored locally. The original PDF is not retained on our servers or stored locally in offline mode.
Offline Mode Limitations
While offline mode gives you full access to core tracking features, some capabilities are only available with an account. In offline mode, original PDF documents are not stored (only extracted data), symptom photos cannot be attached, you cannot sync data between devices, there's no cloud backup (data is lost if you clear browser data), family profiles are not available, and you cannot share records with healthcare providers. The local storage is also limited to approximately 50MB.
What Happens to Your Data in Offline Mode
Your data is encrypted and stored in your browser's IndexedDB. It persists as long as you don't clear your browser data. However, if you switch browsers, use a different device, clear browser data, or uninstall the browser, your data will be lost. We strongly recommend creating an account for data safety, or at minimum, using the export feature regularly to backup your data.
Creating an Account: Online Mode Benefits
When you create a free account, you unlock the full power of JanusMed. Your data is securely synced to our encrypted cloud storage, giving you automatic backup protection. Access your health records from any device — phone, tablet, or computer. Store original PDF documents and symptom photos without size limits. Manage health profiles for your entire family. Share specific records with doctors or family members. Your data is always encrypted, both in transit and at rest.
How Online Sync Works
With an account, JanusMed creates a bi-directional sync between your device and our secure cloud. Changes you make on any device automatically sync to all your other devices. We use TLS 1.3 encryption for all data in transit, and your data is encrypted at rest on our servers. A local cache on your device allows you to access recent data even when temporarily offline — changes queue up and sync when you're back online.
Migrating from Offline to Online
Already using JanusMed offline and want to upgrade? When you create an account, you'll be prompted to migrate your existing local data. Choose 'Yes, sync my data' to upload everything to the cloud — exams, symptoms, medications, all of it. You'll see a progress indicator as each data type is uploaded. Once complete, your local data becomes a cache, and everything is backed up securely. Alternatively, choose 'Start fresh' if you prefer a clean slate.
The Sync Indicator
When you're logged in with an account, you'll see a lightning bolt icon next to your profile in the header. This indicates your data is syncing to the cloud. Tap it to see your sync status: when data was last synced, and an option to manually trigger a sync. If there's an issue with syncing (like network problems), the indicator will show you. You're always in control and always informed about where your data is.
Data Security in Both Modes
Whether you choose offline or online mode, JanusMed prioritizes your data security. In offline mode, data is encrypted using the Web Crypto API with keys derived from your device. In online mode, we add server-side encryption, regular security audits, and HIPAA-aligned practices. We never sell your data, never use it for advertising, and never share it with third parties without your explicit consent.
Making the Right Choice for You
Choose offline mode if you're privacy-focused and want data to never leave your device, you're testing JanusMed before committing, you're using a shared or public computer, or you only need basic tracking without sync. Choose online mode if you want your data backed up securely, you use multiple devices, you want to store original documents and photos, you manage health records for family members, or you want to share records with healthcare providers.
Offline Mode Data Flow
When you use JanusMed without an account, all your data stays on your device.
In offline mode, only the document is sent for biomarker extraction. The extracted data returns to your device and is stored locally. No personal information is kept on JanusMed servers.
Online Mode Data Flow
With an account, your data is securely synced to the cloud for backup and multi-device access.
In online mode, all your data is securely synced with JanusMed cloud. You get automatic backup, access from any device, and additional features like sharing with doctors and family profiles.
Feature Comparison
| Feature | Offline Mode | Online Mode |
|---|---|---|
| Exam Upload & Biomarker Extraction | ✓ | ✓ |
| Original PDF Storage | ✗ | ✓ |
| Symptom Tracking | ✓ | ✓ |
| Symptom Photos | ✗ | ✓ |
| Medication Tracking | ✓ | ✓ |
| Food & Lifestyle Logging | ✓ | ✓ |
| Health Profile | ✓ | ✓ |
| Vaccination Records | ✓ | ✓ |
| Cycle Tracking | ✓ | ✓ |
| Trend Visualization | ✓ | ✓ |
| Data Export | ✓ | ✓ |
| Cloud Backup | ✗ | ✓ |
| Multi-Device Sync | ✗ | ✓ |
| Family Profiles | ✗ | ✓ |
| Share with Doctors | ✗ | ✓ |
| Mobile App Sync | ✗ | ✓ |
Important Tips
- If using offline mode, export your data regularly to avoid losing it when clearing browser data
- Create an account before switching devices or browsers to preserve your data
- You can start offline and upgrade to online mode anytime without losing data
- Check the sync indicator periodically to ensure your data is being backed up
- Use the data export feature before making any major changes as an extra precaution
- For shared computers, consider logging out after each session for privacy
Start for free — no account needed to try it out.