Curtsy Builds a Multichannel Communication Strategy Fit for a Mobile-First Company

Curtsy is a women's clothing resale marketplace app that makes it exceptionally easy to buy and sell clothes. Unlike other resale apps, Curtsy caters to casual sellers — everyday women who appreciate the unique value, sustainability, and options that resale offers, but don’t have the time to dedicate to a high-touch sales process.

Most users today are familiar with a digital resale process from using popular platforms such as craigslist or eBay. On a basic level, reselling involves creating a listing and shipping an item when and if it sells. Pricing, photographing, and tagging items in order to build a more appealing listing can be a time-consuming process for users — especially if they’re selling multiple items. If you account for the added time spent messaging buyers, promoting listings, and managing shipping, the level of time and expertise required to succeed can become a significant barrier to entry.

Curtsy remedies this problem and streamlines the resale process with machine learning. From the moment a user creates a listing, the app pre-fills listing details, recommends an optimal shipping option and price, and sends users everything they need to ship an item before it sells. Whereas other resale apps favor established sellers, Curtsy prioritizes the items being sold (the brand, quality, popularity, etc.).

As Curtsy’s CEO and co-founder David Oates puts it, “Curtsy is more like TikTok than Instagram in that it doesn’t matter how many followers you have, all that matters is the content itself. That means that top sellers don’t have a leg up over new users.” By building a more algorithmically-driven product, their goal was to create a more equal and accessible market for all types of users.

Before Curtsy was a retail app, it started as a platform for women to rent dresses locally. Reflecting on the flagship product, Oates explains, “there were a lot of behavioral triggers, moving parts, and back and forth for each transaction.” That meant that finding the right messaging platform was a vital part of their product strategy.

“This was a day one need for us — we needed transactional notifications in order for that process to work. Traditional companies use email for transactional messages. Since we’re a mobile-first company, we need push notifications.”

Because Curtsy targets inexperienced (i.e. casual) users, it’s paramount that their app experience is seamless, efficient, and straightforward from the moment a user downloads the app. That’s no easy feat when you consider the level of communication and logistical precision digital resale demands. To deliver on their core value proposition, they’ve built a robust customer messaging strategy that leverages mobile push notifications, in-app messaging, and SMS.

As Oates and his team considered different messaging providers, OneSignal emerged as a clear choice. Like Curtsy, OneSignal was a Y Combinator startup and paid homage to their roots by offering a robust free plan and accessible scaling options for early-stage companies. Oates recalls that OneSignal seemed more straightforward than Airship and allowed him to start using the platform immediately, without talking to a salesperson — all things which helped Curtsy move quickly and achieve results at a critical stage in their growth.

For Curtsy, push notifications have been a versatile medium. Oates explains, “I really view push as a re-engagement tool. In the past, product and marketing were fairly siloed — we try to think of them as extensions of each other, one unified system.”

Curtsy uses push notifications to share order tracking information, to send alerts to ensure that sellers ship orders on time, to notify users about messages they’ve received, and to provide recommendations to help novices move inventory. All in all, Oates estimates that it takes between 20 and 30 messages to execute a single transaction. To ensure that each message is perfectly timed within the user journey, Oates used Data Tags to identify specific engagement behaviors, segment users, and automate the messaging process.

As their product and business model evolved, so did their user messaging needs. After setting up transactional notifications, Curtsy started using push notifications to increase app engagement and drive revenue and saw immediate results. Notifications for app-wide sales generated more simultaneous clicks, conversions, and app engagement than Curtsy had anticipated. But reaching this huge growth milestone also brought new challenges.

The Challenge

Unlike transactional notifications, promotional messages needed to be sent to a much larger audience within a limited timeframe. As Curtsy’s user base grew, the overwhelming amount of app traffic generated by promotional messages began stressing their infrastructure and slowing down their product. Although more engagement and users was a good thing, Oates faced a unique hurdle:

“It was a funny problem that was proportional to our size. If you’re just starting out with 100 subscribers, then you’re fine sending to all of them at once. When you hit 1,000 and then 100,000 users, you need to improve your infrastructure — and, like every startup, we constantly need to keep up with that growth.”

The Workaround

As Curtsy worked to scale its infrastructure, Oates worked to come up with a more immediate fix. Rather than scheduling a promotional message for a specific time, he started using OneSignal’s Intelligent Delivery feature to space out message sends and reduce the amount of simultaneous app traffic.

Although this strategy alleviated some pressure, the Intelligent Delivery feature was built to optimize message send time based on user activity, not to control audience size and traffic. Furthermore, the optimal send time can vary greatly between users, which isn’t ideal for limited-time promotions.

So, Curtsy did what scrappy startups do best: they created a custom workaround to overcome these hurdles. To make sure that the app could handle the surge in traffic, they used the Intelligent Delivery feature and built a script to help standardize traffic flow. Although this script worked, it was incredibly finicky and time consuming to run.

Collaborating with OneSignal to Build a Better Solution

Nearly three years later, Oates was struck by another thought: “It just dawned on me one day that we should talk to OneSignal about it — that you’d want to know if we hadn't been able to use the product as intended.”

He reached out to OneSignal, described his experience, and instantly became the inspiration for a new feature: message throttling. Using Oates feedback as a blueprint, OneSignal built a feature that would allow users to control how many messages were sent per minute in order to align traffic volume with server capacity. “This was a complete game changer for us,” says Oates. He only wishes he'd connected with OneSignal sooner. In addition to preventing server overload, the throttling feature also enabled Oates to schedule promotional message sends rather than manually overseeing the process — a feat that has freed him up to work on other projects.

In addition to using push notifications, Curtsy also uses SMS to provide targeted order support in the event that an order doesn’t ship on time. They chose SMS for this particular use case because it allows for back-and-forth conversation between the user and their AI-driven infrastructure. If the data in their system implies that an order hasn’t been shipped by the ETA on file, their system must determine whether to cancel the order and notify the customer. Even though this process is automated, it requires a conversation with the user to figure out what went wrong and what action to take. “We could use in-app messaging for this — but we needed to ensure that the customer sees it immediately, even if they’ve exited the app.” Based on the buyer’s SMS response, the system will automatically cancel the order through Twilio and send an update to the buyer.

In addition to using push notifications, Oates promotes app-wide sales through in-app messaging. He’s just beginning to build out their in-app messaging strategy, but is excited about the growth potential this channel provides. Using OneSignal’s in-app triggers and Data Tags, he plans to send more targeted offers and rewards to drive engagement, increase loyalty, and boost revenue. Rather than launching app-wide sales, he envisions creating a promotional campaign specifically for high-spending customers, as well as campaigns to congratulate sellers when they reach different revenue milestones.

“Instead of doing one-off [marketing] campaigns — which is still important — we want to focus on creating re-engagement loops that are automatically delivered and will scale up with our user base to grow retention and lifetime value.”