Checkout Buddy is a public, third-party app that enables Shopify merchants to customize their checkout with upsell offers, discounts, custom form fields and validations. Merchants can configure the app directly in the checkout and accounts editor without touching a single line of code. Kyle Truong, creator of Checkout Buddy, shares how he leveraged Shopify Extensions in Checkout and saw a 7X increase in monthly app installs within just 4 months.
Hear directly from Kyle Truong, creator of Checkout Buddy
I didn’t start out as an app developer. My degree was in biology, which led to an insurance sales job that I didn’t enjoy. I was looking for a way to gain more freedom and creative potential, which eventually led me to software development. I rediscovered my love for programming and taught myself several programming languages. Starting with Python, I then learned JavaScript and React, ultimately becoming a full-stack developer and creating apps that solve real merchant problems.
The challenge: delivering no-code checkout customizations for merchants
After connecting with other developers and seeing the need for accessible commerce tools, I decided to tackle a common problem for merchants. They often want to enhance their checkout process with upsells, custom banners, and personalized offers but can't do it easily without custom code. I saw a chance to create a solution that makes these enhancements simple to implement.
The opportunity: using Shopify Extensions to build a powerful checkout app
I had to create an intuitive experience for merchants to add complex customizations. Shopify Extensions are how apps can extend and customize functionality across Shopify. For checkout, in particular, I saw the opportunity to build Checkout Buddy using checkout UI extensions at its core.
My development process began with sketches on paper, mapping out where widgets should go before building them using these UI extensions. Shopify's documentation helped me understand how to work with these APIs. This approach led to adding elements like upsells, trust badges, and banners. I was also able to package functions and the branding API on top of the extension APIs into one cohesive app.
My development workflow became simple: study the documentation, code the feature, test thoroughly, deploy, and gather merchant feedback. I didn’t have to worry about a host of extensions-related issues, such as security or big upgrade cycles, because the customizations run in a sandbox in the browser, and the extensions are upgrade-safe. This meant more time for my actual feature development!
All said and done, the overall developer experience from the get-go, be it Shopify CLI 3.0, tutorials, interactive API explorer, and more, cut down on development time, leading me to build over 10+ custom functions and 30+ UI extensions into Checkout Buddy.
The results: increasing monthly app installs by 7X
When I launched Checkout Buddy, I faced the classic startup challenge: how to get my app in front of merchants who needed it. As a solo developer with no marketing budget, I worried about gaining traction in a crowded marketplace. I quickly realized that the App Store itself was solving part of my distribution problem. Merchants were actively searching for checkout customization solutions, and my app was appearing in their results.
I decided to focus on two key strategies: offering a free plan to eliminate barriers to trying the app and encouraging satisfied users to share their experiences. This approach required patience at first, as growth started modestly. Rather than spending time on marketing campaigns, I channeled my energy into improving the product based on user feedback. I prioritized the features merchants requested most, particularly upsell and cross-sell capabilities.
Word-of-mouth recommendations combined with App Store visibility created a snowball effect. Monthly installs grew 7X within four months, and I was able to release 74 new features during the first year.
The app now has a growing user base of merchants who are seeing real results in their checkout performance. Some users have even suggested I increase pricing based on the value they're receiving. This success has convinced me that focusing on product quality over marketing was the right approach for my app.
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