How Doorlist keeps guests in the loop with real-time RCS messaging

Doorlist makes it easier to bring people together. Founded in 2023 by David Roselle while he was still in college, the platform helps anyone host gatherings of five to 5,000 people – from friend groups to large-scale events – across the US.

And none of that works if the messages don’t arrive on time.

“Even a five-minute delay can be extremely destructive to the host experience and the guest experience,” said David, CEO of Doorlist.

Hosts use the platform to send real-time updates to hundreds of guests at once – last-minute logistics, safety notices, pre-event buzz. A late message isn’t just an inconvenience. It’s a failure.

By late 2024, that’s exactly what was happening.

Doorlist’s traffic doesn’t follow a 9-to-5 schedule. Usage spikes sharply on Thursday, Friday, and Saturday nights when hosts are most likely to send time-sensitive updates.

Their previous providers could handle the overall volume in theory. In practice, the system buckled under pressure. Halloween made that impossible to ignore. Hosts sent blast messages to their guests, and those messages sat in a queue for four to five hours. Users were getting texts at 2 AM that had been sent at 9 PM – some with information that mattered in the moment.

“That was really the straw that broke the camel’s back,” David said. “It was time to find a provider who could support us not just today, but also as we grew.”

There was a second problem. Every message Doorlist sent arrived from a random phone number – no logo, no name, no context. For new users receiving their first event invite, it was a confusing first impression from a brand they hadn’t learned to trust yet.

Doorlist had looked into Rich Communication Services (RCS) as a fix, but providers kept closing the door. Some said RCS was reserved for Fortune 500 companies. Others quoted approval timelines of 12 to 18 months.

Doorlist found Sinch through a mutual connection – someone who’d used the platform and recommended it. The first call made it clear that this was different.

“I remember hanging up thinking, not only do I think we might have a great partner here, but they seem to really deeply understand our business,” David said. “We had a really good roadmap of what a relationship would look like, even in just a 45-minute call.”

Sinch started working through the RCS approval process before the contract was even signed – pre-filling forms, preparing documentation, and building carrier relationships in parallel.

“They took a risk on investing their time in making sure we could be approved,” David said. “The day the agreement was signed, almost all of the paperwork was done.”

Doorlist signed its contract in mid-January. RCS messages were reaching users by early February.

“We knew it would be fast based on our conversations,” David said. “I don’t think we appreciated how fast it would be. If it had taken any longer, we would have still been on antiquated technologies that don’t resonate with users as much. We probably would have grown more slowly.”

At a platform growing as fast as Doorlist, a significant chunk of users at any given moment are brand new. The first message they receive – an event invite from a friend – is also their first encounter with Doorlist as a product.

With RCS, that message now looks like Doorlist. The brand’s logo and name appear at the top. The look and feel matches the app. And because they’re a verified sender, users know the message is legitimate before they’ve even read it.

Doorlist now uses Sinch RCS for Business for two core touchpoints: event invitations that drive the initial RSVP and host text blasts that reach every guest at once without needing anyone’s phone number. For gatherings in the 40-to-60-person range – too big for a group chat, too personal for a mass email – that kind of direct, branded communication is what makes the experience work.

For David, Sinch isn’t just solving today’s problem. It’s the foundation for how Doorlist communicates as it grows.

“One thing that was really exciting is being able to build with more of the Sinch products in the future – email, voice, the whole array of services under one platform,” David said.

The team is already thinking about how RCS can extend further into the product – not just for notifications and blasts, but as part of the social layer that makes Doorlist distinct.

“Before, it was much more of a customer-to-vendor relationship,” David said. “With Sinch, it’s a very obvious long-term partnership.”