"With Cello, we’ve unlocked a cost-efficient new channel for growth. Referrals bring us paying customers at one-tenth the cost of paid ads."

Katerina Simonova, Growth Marketer (Softr)

0%

Referral View-to-Signup Conversion Rate

0x

Lower CAC than paid ads

0-figure

ARR contribution

HQ
Berlin, Germany
Funding
Series A
Employees
51–100
Category
No-code website & app builder
Pricing
Freemium
Customers
B2B & B2C
Customer with Cello
Since 2025

How Softr turned referrals into a low-cost growth lever

Berlin-based Softr, a leading no-code website and app builder, was searching for a way to diversify its acquisition mix beyond paid ads and affiliate programs. While those channels performed well, CAC was climbing, and they wanted a more cost-efficient way to convert engaged users into customers.

Softr’s earlier referral program, run on PartnerStack, lacked the flexibility they needed. It required end users to register on PartnerStack, which added friction, and payouts were harder to access. Softr also wanted a sleeker widget, the ability to A/B test, and a more user-friendly copy/paste sharing flow.

Although it drove thousands of signups, fewer than 2% converted to paid customers. Each click was worth less than $1 in revenue on average.

That’s where Cello came in.

Free-to-Paid Conversion Rate: PartnerStack vs. Cello

How did they succeed?

A simple, clear reward structure

Softr introduced a straightforward “Earn $50” reward, making the referral value proposition easy to understand and act on.

Seamlessly embedded with the Custom Launcher

Using Cello’s Custom Launcher, the referral program was placed directly into Softr’s top-right menu, ensuring discoverability when users looked for support, product updates, or feedback. Later, Softr also added the launcher inside the My account secondary menu, making it accessible in multiple places while balancing prominence with product simplicity.

Passive visibility, front of mind at the right moments

Instead of relying on Cello emails or announcements, Softr chose a low-noise setup, trusting in-product visibility to keep referrals front of mind. The program was accessible in the same menus users already relied on for support, product updates, and account settings, making referrals easy to find without disrupting their workflow.

The result?

Within months, Softr’s referral program was generating consistent paid customers and recurring revenue.

  • Referrals delivered a strong five-figure ARR contribution, with high-value customers converting from the channel.
  • They became a growing share of new MRR, complementing ads and affiliates.
  • Best of all, CAC was 10x lower than paid ads, making referrals one of Softr’s most cost-efficient acquisition levers.

Competitor comparison: With PartnerStack, fewer than 2% of signups became paid customers. With Cello, nearly 10% of referred signups upgraded from free to paid, a fivefold improvement.

Looking ahead

Softr now has a scalable, cost-efficient growth loop in place. Referrals may not yet be their largest acquisition lever, but they are among the most efficient and highest-quality sources of new customers.

By refining rewards and boosting visibility, Softr plans to expand the program further, embedding referrals even deeper into their growth motion.