long story short
- Users who have rooted their phones, unlocked the bootloader, or are using certain custom ROMs have reported that their RCS messages are not being sent even though RCS shows connected.
- When blocking RCS messages from these users, the Google Messages app will not display any error messages and the messages will not be sent as SMS or MMS messages.
- Google has strongly pushed Apple to add RCS messaging functionality to iMessage, but now it has blocked this feature from some Android users.
Updated: March 1, 2024 (12:35 PM ET): A Google spokesperson has been contacted Android Authority and issued the following statement:
– Ensuring that messaging sending/receiving devices follow operational measures defined by RCS standards is one of the ways Google Messages prevents spam and abuse.
– When we fight spammers and fraudsters, we consider different metrics. A large amount of RCS spam comes from automation, which often relies on modifications to the sending device.
– Our spam prevention technology is constantly evolving to respond 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 text: March 1, 2024 (4:46 a.m. ET): We’ve all seen Google wax poetic and insistent about how RCS messaging is the best thing since sliced bread, and how Apple should adopt the standard on its iPhone to bring a great messaging experience to all users. We agree, and even Apple has promised to bring RCS to iMessage this year, likely in the upcoming iOS 18 update. But while Google wants others to use RCS, the company is blocking users of rooted Android phones and custom ROMs from using it on their devices.
Many users complained on Reddit (h/t mishal rahman) Google is quietly blocking RCS messages on Rooted devices and custom ROMs. More specifically, Google appears to have started implementing Play Integrity API attestation checks (often called “SafetyNet checks”, inspired by the predecessor SafetyNet API) on the Google Messages app.
NOTE: Users report that the Google Messages app will not allow them to send or receive RCS messages if the operating system is rooted or has not been GMS certified (as with most custom ROMs).
The Play Integrity API and its predecessor SafetyNet API are anti-abuse APIs used to check the integrity of Android devices. These APIs will throw errors if the Android device has been tampered with in any way, such as unlocking its bootloader to install a custom ROM or gaining root privileges. Applications checking for this error can recognize that the device is not in stock and can react accordingly, often refusing to work.
The most logical intended use is for applications with high security requirements, such as banking applications. Nonetheless, there is a growing trend for applications with relatively low security requirements to also use these checks. This results in the locking of rooted phones and phones with custom ROMs for vague reasons.
With Google Messages, Google won’t even throw any errors that the user is locked out of RCS. In the video above, RCS appears to be enabled (as shown in the chat text box), but the sent message disappears without a trace. These messages are also not processed as SMS/MMS fallback unless you turn off the RCS feature.
You might blame your phone or carrier for this behavior, not realizing that Google blocked RCS from running on your phone without clearly explaining why. Users must independently investigate the issue to understand the SafetyNet check on the Google Messages application.
Google mentioned 9 to 5 google Some of these phones were banned from using RCS, citing the need to prevent spam and abuse through “operational measures” that ensure devices adhere to RCS standards.
SMS and MMS continue to work on rooted phones with unlocked bootloaders. But they do this on the iPhone, too, so Google’s stance does seem rather hypocritical.
If you’re smart enough to root your phone or unlock the bootloader to install a custom ROM, you can bypass the check using the Play Integrity Fix Magisk module. However, it’s a cat-and-mouse game where you’re constantly competing with Google for the privilege of sending RCS text. Maybe it’s time for Google to get the message too? In the meantime, you can use other messaging applications that support RCS.
We’ve reached out to Google for more information and a statement. We will update this article when we hear back from them.