Mobile health services protect sensitive patient interactions by securing the data at each place it appears on the phone, then choosing responses that keep care within reach. Otukan encrypts records the app caches, limits what stays in memory, checks the connections that carry clinical data, proves to your services that requests come from the genuine app, and recognises remote-control scams during sensitive steps. Each flow gets its own graded response and fallback. Otukan covers the app on Android and iOS; your backend, your managed devices and your clinical safety processes keep their own responsibilities.
Data exposure
Patient data passes through four places in a mobile app. Each needs its own control.
Records and cached data
Results, letters, images and messages are often cached for offline use. On Android, Otukan encrypts them with keys held in the Android Keystore, which is hardware-backed on devices that support it. On iOS, records sit under a Data Protection class that keeps files unreadable while the device is locked, with keys in the Keychain. The two platforms work differently and Otukan implements each on its own terms. For detail, see Android app data encryption and iOS app data encryption.
Authentication
Sign-in tokens and biometric unlock guard the whole record. Otukan attestation lets your services confirm each request comes from the unmodified app, so a copied token replayed from a script stands out. Attestation is covered on mobile app attestation.
Memory
Decrypted records exist in memory while a patient or clinician reads them. Otukan limits how long they stay there, clears them when a sensitive view closes, and detects debuggers and hooking frameworks that try to read them.
Communication
Messages, record downloads and consultation set-up travel over the network. Otukan checks server identity on those connections and refuses certificates the app does not expect.
| Where data appears | Typical exposure | Otukan control |
|---|---|---|
| Local cache | Readable files on a rooted or jailbroken phone | Encryption with platform-protected keys |
| Sign-in token | Replay from another device or a script | Attestation on every sensitive request |
| Memory | Extraction with debugging or hooking tools | In-memory data protection, runtime detection |
| Network | Interception through hostile networks | Server identity checks on connections |
| Screen | Remote viewing during a coached call | Remote access and screen sharing signals |
How Otukan handles the signals it sends is covered on mobile app security data privacy.
Clinical continuity
Proportionate responses
Health apps carry flows of very different urgency. Otukan’s response policy is graded per flow, so a risk signal restricts the risky action rather than locking the patient out of the whole app.
| Flow | Response on a suspicious device |
|---|---|
| Emergency contacts and care guidance | Stays available |
| Appointments and reminders | Available, with a warning |
| Viewing results and records | Live view only; offline copies withheld |
| Prescription renewal, record export, account changes | Stronger verification or an alternative channel |
Failure modes
A check can fail for innocent reasons: no network, an old device, an operating system update. Each flow has a defined fallback, agreed with your clinical and product teams, and new signals start in observe mode so their effect on genuine patients and clinicians is measured first. Policy can change without a new app release.
Responsibilities
Otukan protects the app. Other parts of the service keep their own duties, and naming them avoids gaps.
- App controls (Otukan). Encryption on the device, runtime detection, attestation, connection checks and graded responses.
- Backend. Access control, consent, audit logging and the final decision on every request. Otukan’s signals inform it.
- Devices. Clinician devices issued by your organisation are enrolled and administered by device management, a separate responsibility.
- Clinical assurance. Clinical safety cases and any medical device software obligations remain your organisation’s own processes.
Otukan maps each control to a public mobile security standard with its platform scope and test records; for the mapping, see OWASP MASVS mobile app security. That mapping supports your assessment and is not a certification.
For the full set of Otukan app controls, return to mobile app security. Health apps already published can start with a free App Exposure Check, which looks only at the public store build.