But then there's still the privacy issue. Messages sent on many OTT messaging apps, including iMessage and WhatsApp, are end-to-end encrypted, meaning they can't be read by anyone but the sender or recipient. RCS messages are not, though Google says it's working on a solution to provide more privacy to users.
Until it does, it could be difficult to convince consumers to use the service, especially as end-to-end encryption inches closer to industry standard. Facebook, for one, has made it one of the six principles of its "privacy-focused vision" and said it plans to encrypt messages on Instagram and Messenger as well.
How could RCS affect existing OTT mobile messaging apps?
Marketers interviewed for our upcoming report, "Global Messaging Apps 2019," had mixed feelings about how RCS could affect use of existing OTT mobile messaging apps. Having a built-in messaging service that can send messages across operating systems via a data connection could negate the need for a standalone app that serves the same purpose.
But many OTT messaging apps have additional features that will make them hard for consumers to give up completely.
"The eventual rollout of RCS will definitely impact users who use mobile messaging apps solely to send messages," said Chelsea McDonald, senior social media strategist at DEG Digital. "But consumers who use features that make those apps more of a social experience and not just one-to-one messaging are going to stick with what they know."
WhatsApp, for instance, has Status—disappearing photos and videos like those on Facebook, Instagram, Messenger and Snapchat Stories. WhatsApp Status had more than 500 million daily active users worldwide in Q1 2019, per Facebook. Then there's China's super-app WeChat, which allows its users to do almost anything from send a message to hail a ride or shop online.
"Mobile messaging services are going to have to get a lot more creative with new features as phone manufacturers and service carriers start competing in the space," said Akvile DeFazio, president of social media marketing agency AKvertise.
But there's still a long road ahead for a worldwide rollout of RCS, and until it's available more broadly, the impact on the mobile messaging app space is likely to be small.
For more analysis on messaging apps, be sure to read our Global Messaging Apps 2019 report when it publishes in September.