Türkçe sürüm / Turkish version

GrapheneOS, the privacy and security focused Android-based operating system, answered CyberNews's questions. According to the project, the bigger threat is not Google's Android developer verification but the Play Integrity API, which checks Google certification rather than security and locks alternative operating systems out of banking and government apps.

As part of our Keep Android Open dossier, CyberNews asked GrapheneOS on 31 October about Google's mandatory Android developer verification. In its first reply, the GrapheneOS team said the rule does not directly apply to GrapheneOS and pointed to the Play Integrity API instead. We then sent four follow-up questions, which Andrew Fenton answered on behalf of GrapheneOS. The interview was conducted in English by email; the answers below are published in full as given.

GrapheneOS's first reply to our interview request:

Android developer verification doesn't apply to GrapheneOS. It applies to Google Mobile Services operating systems. It impacts developers who don't want to share their real identity with Google in order to make Android apps. It takes the form of a scary warning with a toggle for bypassing it which requires a 24h wait to enable for the first time. The delay can be avoided via developer options via Android Debug Bridge by power users.

It would make much more sense to focus on the Play Integrity API. It's far more harmful, far more clearly anti-competitive and they have such a flimsy justification for the way it works pretending it's a security feature when it clearly isn't.

Google's Play Integrity API is largely a system for banning alternatives to Google Mobile Services operating systems. It impacts each alternative OS even if those aren't based on the Android Open Source Project. It has an extremely negative impact on GrapheneOS and is nearly the only cause of app compatibility issues which can't be worked around. Nearly every Android app can be used on GrapheneOS, but not ones enforcing Google certification with the Play Integrity API device and strong integrity levels. Apps and services are gradually adopting the Play Integrity API device and strong integrity levels which makes those unavailable on any alternatives to Google Mobile Services Android. This gradually hurts compatibility with GrapheneOS.

Play Integrity API device integrity level permits devices with a decade of no security updates. Strong integrity level has a limit of not being more than 1 year behind on the Android Security Bulletin patch level which is 2-6 months behind when patches are first made available to OEMs to ship. That means it permits being up to around 1.5 years behind. It also has a blanket exception for OS versions older than Android 13 being an arbitrary level behind. Any device launched with Android 8 or later can pass the strong integrity level with the stock OS even with zero security updates since launch. This clearly demonstrates neither level is intended to be a real security check. It's intended to lock out any alternative by checking for Google certification, which is the primary thing both actually check. This is one of the primary ways Google is eliminating the possibility of having competitive with their monopolies in multiple spaces on mobile.

Andrew Fenton (GrapheneOS), before answering our follow-up questions:

Play Integrity is a very complex topic, but I'll try to keep it as brief and to the point as possible...

When implemented, apps usually check for either the "basic" or "strong" integrity verdicts. GrapheneOS can pass the "basic" integrity verdict but only if the user is logged in to Google Play and the app is installed using Google Play, so many of our users are forced to log in and use Google Play to install certain apps even when they would prefer not to.

Apps on GrapheneOS can not receive the "strong" integrity verdict. A requirement for the "strong" integrity verdict is the "device" integrity verdict, which requires: "On Android 13 and higher, there is hardware-backed proof that the device bootloader is locked and the loaded Android OS is a certified device manufacturer image."

Verdicts are documented here: https://developer.android.com/google/play/integrity/verdicts

1. In simple words, how does the Play Integrity API block alternative operating systems like GrapheneOS?

Google uses cryptography to make getting the "strong" or "device" integrity verdicts impossible for operating systems like GrapheneOS simply because they aren't "certified" by Google. Certification/licensing, not security, is the deciding factor. Google convinces developers to use Play Integrity and developers then inadvertently ban GrapheneOS users from using their apps or using certain app functionality despite GrapheneOS being objectively more secure than other operating systems that can receive "strong" integrity verdicts.

2. Which kinds of apps (for example banking or government apps) cause the most problems for GrapheneOS users?

We're aware of both banking and government apps using Play Integrity to ban GrapheneOS. The number of apps using Play Integrity has been increasing as Google increasingly advises developers to use it.

3. What should app developers use instead, if they want real security checks?

If app developers want "real security checks" then they should not rely on Play Integrity at all since they're so lax about security for strong integrity verdicts.

App developers can use the standard hardware attestation API to permit OSes that meet their requirements. Instructions on how to use the API to add GrapheneOS can be found here: https://grapheneos.org/articles/attestation-compatibility-guide.

4. Do you think regulators, for example under the EU Digital Markets Act, should act on this?

Absolutely. For example, the DMA has its rules but allows gatekeepers some leeway if security is a concern. Although developers aren't being forced to use Play Integrity, Google has been increasingly advising developers to use it for "security" reasons. Play Integrity even shows up on this security checklist: https://developer.android.com/privacy-and-security/security-tips#app_integrity. Misleading developers so they use Play Integrity to cause friction for people using operating systems that aren't certified by Google is clearly anti-competitive. The feature itself is anti-competitive.

Interview conducted by email, 31 October – 4 November 2026. The first statement is by the GrapheneOS team; the answers to the follow-up questions are by Andrew Fenton on behalf of GrapheneOS, published with GrapheneOS's permission. Turkish version: GrapheneOS: Play Integrity güvenlik değil, rekabet engeli.

More from the Keep Android Open dossier: https://cybernewsturkey.com/etiket/keep-android-open