Shopify has over 8,000 apps in its marketplace, covering everything from post-purchase upsell flows to subscription billing, SMS marketing, loyalty programs, review aggregation, and bundle builders. The apps a successful store chooses reflect years of testing, A/B experiments, and hard-won knowledge about what moves metrics for their specific customer base. If you're building or scaling your own Shopify store, knowing what Shopify apps a competitor runs is one of the fastest shortcuts to not reinventing the wheel.
And here's the thing: almost every Shopify app leaves a detectable signature. Some load JavaScript on the storefront. Some inject HTML. Some set cookies or load assets from their own CDN. You just need a way to read those signatures without spending an hour in DevTools for every store you want to research.
First: Confirm They're on Shopify
Before hunting for specific apps, confirm the store is actually running Shopify. The telltale signs:
- The
cdn.shopify.comdomain appears in script or image sources Shopify.themeis accessible in the browser console- The checkout subdomain is
checkout.shopify.comor a custom domain routing through Shopify's infrastructure - HTTP response header
x-shopify-stageis present - Cart endpoint
/cart.jsreturns valid JSON
Using SaaS Detective, the platform detection is instant — Shopify shows up in the E-Commerce category the moment you click the extension icon on any Shopify storefront.
Category 1: Email and SMS Marketing Apps
These are among the most detectable Shopify apps because they load client-side scripts for popup forms and tracking. Key signatures:
- Klaviyo —
static.klaviyo.com/onsite/js/klaviyo.jsand the_kxcookie; extremely common on mid-to-large Shopify stores - Attentive —
cdn.attn.tvloads for their SMS sign-up widget - Postscript —
js.pstmrk.itfor their SMS tools - Omnisend —
omnisrc.comscripts - SMSBump (Yotpo) —
cdn.smsbump.com
Seeing Klaviyo on a competitor's store tells you they're serious about email — likely running sophisticated flows for abandoned cart, welcome series, and post-purchase. Attentive alongside Klaviyo suggests a mature retention stack with both email and SMS covered.
Category 2: Reviews and Social Proof
Review apps are highly detectable because they inject star rating widgets and review carousels directly into product page HTML:
- Judge.me — loads from
cdn.judge.me - Stamped.io —
cdn1.stamped.ioassets - Yotpo — scripts from
staticw2.yotpo.com - Okendo —
cdn.okendo.io - Loox —
cdn.loox.iofor photo reviews
Category 3: Upsell, Cross-Sell, and AOV Tools
This category is where significant revenue optimization happens. Watch for:
- ReConvert — post-purchase upsell pages; loads
reconvert.comassets on the order confirmation page - Zipify OneClickUpsell (OCU) — post-purchase upsell with
zipify.comscripts - CartHook — post-purchase offers with characteristic markup patterns
- Frequently Bought Together — injects specific widget containers on product pages
- Bold Upsell —
boldapps.netCDN assets
Most tech stack detectors only scan the homepage. Add a product to a competitor's cart, complete a test purchase (or just reach the checkout), and run SaaS Detective on the order confirmation page. This is where post-purchase upsell apps, loyalty program integrations, and referral tools load — and they're invisible from the homepage.
Category 4: Loyalty and Retention Apps
Loyalty programs are highly competitive and the app choice reflects a brand's retention philosophy:
- Smile.io —
cdn.smile.ioloads the rewards widget - LoyaltyLion —
cdn.loyaltylion.net - Yotpo Loyalty (Swell) — now part of the Yotpo suite
- Stamped Loyalty — runs alongside their reviews product
Category 5: Search and Merchandising
- Searchie / Searchanise — replaces Shopify's native search with AI-powered results
- Boost Commerce —
boost-commerce.netscripts for filtering and search - Klevu —
js.klevu.comfor ML-powered search - Searchpie — loads its own storefront script bundle
A store investing in a premium search app like Klevu signals high SKU count and a serious focus on product discoverability — typically stores with 1,000+ products where native Shopify search breaks down.
Category 6: Subscription and Recurring Revenue
- Recharge —
cdn.rechargeapps.com; the dominant Shopify subscription platform - Bold Subscriptions —
boldapps.net/subscriptions - Skio — newer subscription tool gaining traction with DTC brands
- Ordergroove — enterprise subscription solution
Seeing Recharge or Skio on a competitor confirms they're doing recurring revenue — their LTV math is completely different from a pure one-time purchase model, which changes how you think about their customer acquisition economics.
Putting It Together with SaaS Detective
Manually identifying all of these signatures requires knowing dozens of CDN domains and cookie names. For a systematic competitive audit, SaaS Detective automates the detection across 200+ signatures — including Shopify-specific apps — and presents the results in organized categories. You visit the homepage, run the extension, check the product page, run it again, and check the cart and post-purchase flow. Total time: under five minutes for a thorough app audit of any competitor store.
The extension also catches tools that aren't Shopify-specific but are commonly used alongside Shopify stores — analytics platforms like Triple Whale or Northbeam, ad platforms via their pixels, and subscription tools that load on the checkout domain.
Bottom Line
Detecting what Shopify apps a competitor uses comes down to knowing the client-side signatures each app leaves behind — CDN domains, cookie names, script tags, and HTML markup patterns. For a complete picture, check the homepage, product pages, cart, and post-purchase flow. SaaS Detective handles the detection automatically, turning a 30-minute manual research process into a five-minute competitive audit you can run on any Shopify store, any time. The apps you find reveal not just their current stack — they reveal their strategy.