EU Age Verification: Why Mobile App Security Needs to Go Further

With new EU regulations emphasizing online safety and digital identity, the European Commission has tasked five EU member states—France, Spain, Italy, Denmark, and Greece— to pilot an age verification app under the European Digital Identity (EUDI) framework. The age verification is intended to occur via a mobile app as part of a broader digital identity program to be deployed to almost 500M European citizens by the end of 2026.

For mobile app developers and security teams working in digital identity and wallet ecosystems, this marks a critical shift. Age verification is evolving from a compliance checkbox to a core mobile app security requirement.

What this means for mobile app developers and security teams who build and oversee identity/digital wallet apps is that age verification is becoming a first-class security requirement rather than an optional gate. Yet, the EU’s own prototype app, built on the same foundation as the upcoming European Digital Identity Wallet, has already raised security concerns. Critics note that it relies entirely on Apple’s App Attest and Google’s Play Integrity API for security.

That’s a red flag.

The challenge: Platform-native attestation isn’t enough

Platform-native attestation can confirm that an app is genuine and the device isn’t compromised, but that’s where its reach ends. It doesn’t catch other Man-at-the-end attacks like reverse engineering and app tampering. And, for a system handling sensitive identity data, the dependency on US-based platforms also raises questions about data sovereignty and EU privacy alignment.

As regulators look for scalable, privacy-first ways to verify age, developers and security teams need to evolve their approach. Attestation can’t stand alone; it needs to be part of a broader, multi-layered mobile app security strategy.

Google and Apple both offer attestation APIs that help verify whether a mobile app is:

• Untampered (i.e., it matches the developer’s original code signature)
• Running on a “secure” device (non-rooted/jailbroken, verified boot status)

That’s a helpful foundation, but in the context of regulated age verification flows, it’s not enough due to the following issues:

Platform lock-in

Google Play Integrity covers only Android; similarly, Apple App Attest covers only iOS devices. This makes implementations more complex and costly to maintain for app publishers.

Data sovereignty

Age verification requires sensitive identity/age data; delegating that entirely to US-based platforms raises concerns for EU jurisdictions, sparking debates among developers on Reddit and Github.

Single-layer protection

Google Play Integrity and Apple App Attest verify app integrity or environment, but don’t address what happens inside the app, such as reverse engineering and tampering attacks.

Regulatory compliance

Regulatory frameworks such as the EU Cyber Resilience Act and ENISA guidance emphasize tamper resistance and runtime protection, capabilities that OS-level attestation alone doesn’t deliver.

Relying solely on Play Integrity or App Attest shows several limitations. Developers must implement additional controls to ensure trust in the device, the user, and the verification flow.

What mobile app security standards, like OWASP, recommend

The OWASP Mobile Application Security Testing Guide (MASTG) and the related OWASP Mobile Application Security Verification Standard (MASVS) recognize attestation as one of many security controls.

The MASVS‑Resilience domain (formerly MASVS‑R) emphasizes that attestation must be complemented with controls for tampering, reverse‐engineering, emulator detection, runtime integrity, and more.

Hence, relying solely on platform attestation means missing major threat vectors: reverse engineering attempts, app tampering, API interception and exploitation, and more, all of which might bypass a platform attestation check.

Multi-layered mobile app security for age verification

To deliver a secure and regulation-ready age verification experience, developers must go beyond Apple or Google’s attestation APIs and adopt a multi-layered defense approach.

Mobile app security testing

Identifying security issues early in the app development process is essential for protecting sensitive user validation processes like age verification. If an app is vulnerable to tampering or reverse engineering, attackers could bypass the age verification logic, inject fake age data, or manipulate API calls to fraudulently access age-restricted features. To prevent this, it’s critical to:

• Routinely scanning the application throughout the entire software development lifecycle to identify and fix vulnerabilities promptly.
• Automating security scans within the CI/CD pipeline to ensure code is checked at every commit and security remains continuous and proactive.

Code obfuscation and runtime application self-protection (RASP)

Attackers may reverse engineer apps to disable age gates or tamper with how verification requests are sent. Code obfuscation and encryption:

• Make verification logic harder to discover
• Prevent easy repackaging or patching

RASP provides real-time visibility into the app’s behavior and environment. It helps detect:

• Rooted or jailbroken devices
• Debugger connections
• Memory tampering or Frida/Xposed hooks
• Unauthorized runtime instrumentation

These are common tactics used to defeat client-side age verification logic; not all of these scenarios can be detected by App Attest or Play Integrity.

Mobile app attestation

Even if the app uses App Attest or Play Integrity attestation:

• Every access to the API must be validated server-side
• Tokens should be short-lived, bound to specific sessions or payloads
• Access to age-gated content or services should be denied unless all checks pass

This closes the loop between device state and backend logic, making it much harder to spoof access.

Threat monitoring

Security doesn’t stop at setup, it requires visibility to:

• Track unusual account creation spikes
• Flag multiple verification failures from the same IP/device
• Analyze real-time threat patterns to evolve policies

This allows teams to adapt quickly, even if the app is already deployed, helping meet regulatory expectations for active threat response.

Final thoughts

As EU countries roll out age verification pilots, app developers must not assume that Apple’s or Google’s attestation APIs alone will deliver compliance-ready security. These tools verify device integrity but not runtime behavior or code resilience, the areas most exploited by attackers. To build user trust and meet emerging regulatory expectations, mobile app security must go deeper:

• Test and secure your app’s code earlier
• Harden the app against tampering
• Monitor runtime threats continuously
• Validate every API request with attestation
• Adapt rapidly as new threats emerge

Contact a Guardsquare expert to learn how to strengthen your age verification or digital identity app against evolving threats.