Google is silently blocking RCS on rooted Android phones and custom ROMs (Update)

Update: March 1, 2024 (12:35 PM ET): A spokesperson from Google has reached out to Android Authority and provided the following statement:

– Ensuring that message-issuing/receiving devices are following the operating measures defined by the RCS standard is one of the ways Google Messages prevent spam and abuse.

– As we fight spammers and fraudsters, we take into account different indicators. A large volume of RCS spam comes from automation, which typically relies on modifications to the sending device.

– Our spam prevention techniques constantly evolve in response to the changing behavior of spammers. We will continue to look for ways to prevent spam and fraud while minimizing the number of users affected.

Original article: March 1, 2024 (4:46 AM ET): We’ve all seen Google wax poetically and relentlessly on how RCS messaging is the next best thing since sliced bread and how Apple should adopt the standard on its iPhones to bring a great messaging experience to all users. We agree with the sentiment, and even Apple has committed to including RCS in iMessage this year, likely with the impending iOS 18 update. But as much as Google wants others to use RCS, the company is blocking rooted Android phones and custom ROM users from using it on their devices.

Many users are complaining on Reddit (h/t Mishaal Rahman) that Google is quietly blocking RCS messages on rooted devices and custom ROMs. More specifically, it appears that Google has begun implementing Play Integrity API attestation checks (popularly known as “SafetyNet checks,” inspired by the predecessor SafetyNet API) on the Google Messages app.

The Play Integrity API and the predecessor SafetyNet API are both anti-abuse APIs that check for the integrity of the Android device. If an Android device is tampered with in any way, such as having its bootloader unlocked for installing a custom ROM or is rooted, these APIs throw up an error. Apps that check for this error can recognize that the device is not in stock condition and can react accordingly, often refusing to work.

The most logical intended usage for this is for high-security requirement apps, such as banking apps. Still, there has been a growing trend of relatively low-security requirement apps also using these checks. This leads to locking out rooted phones and phones with custom ROMs on vague grounds.

With Google Messages, Google isn’t even throwing up any error that the user is locked out of RCS. In the video above, RCS appears enabled (as seen in the chat text box), but messages being sent simply disappear into thin air. The messages are not going through as SMS/MMS fallback either unless you switch off RCS features.

You might blame your phone or carrier for this behavior, not realizing that Google is blocking RCS from working on your phone without clearly explaining its reasons. Users have had to investigate the issue independently to find out about SafetyNet checks on the Google Messages app.

Google mentions to 9to5Google that some of those phones are prevented from using RCS, citing the need to prevent spam and abuse by making sure devices abide by the RCS standard’s “operating measures.”

SMS and MMS continue working on rooted phones with unlocked bootloaders. But they also do on iPhones, so Google’s stance does appear quite hypocritical.

If you are savvy enough to root your phone or unlock your bootloader to install a custom ROM, you can bypass the checks with the Play Integrity Fix Magisk module. However, this is a game of cat and mouse, and you’d constantly be fighting against Google for the privilege of sending an RCS text. Maybe it’s time for Google to get the message too? In the interim, you can use other messaging apps that support RCS.

We’ve reached out to Google for more information and a statement. We’ll update the article when we hear back from them.