Building a Shopify app in 2026 costs almost nothing:
- Shopify CLI and Polaris are free.
- Gadget hosts a prototype for $0 (up to 5 installs).
- The App Store takes 0% of your first $1M of lifetime revenue.
The expensive part is the first 10–50 merchants, and the App Store won't hand them to a listing with zero reviews. Founders who get there fast run outbound:
- Store Leads (from $75/mo) or BuiltWith finds stores by platform and installed apps.
- SocLeads (free for 100 contacts, Basic $29/mo) or Apollo finds the owner's contact.
- Instantly sends and warms the email.
We build custom Shopify apps and checkout extensions. This is the playbook we hand to founders after launch.
| Tool | Job | Starting price (Oct 2026) | Limit |
|---|---|---|---|
| Shopify CLI + Polaris | Scaffold and UI | Free ($19 one-time Partner fee to list) | You host the backend |
| Gadget | Hosted backend with Shopify sync | $0 Hobby (5 installs), Pro $35/mo | Runs on Gadget's stack |
| App Store revenue share | Distribution | 0% on first $1M lifetime, then 15% | Lifetime, not yearly |
| Store Leads | Find stores by installed apps | From $75/mo | No personal emails |
| BuiltWith | Find stores by technology | From $295/mo | Pricey early |
| SocLeads | Owner contacts from Google Maps and social | Free 100 contacts; Basic $29/mo | A row may not include an email |
| Apollo.io | Decision-makers at larger merchants | Free plan; paid from $49/mo | Credits expire monthly |
| Instantly | Send and warm cold email | From $47/mo | Lead data costs extra |
§ 01Build: Shopify CLI, Polaris and Gadget
shopify app init scaffolds an embedded app on the official template, and Polaris makes it look native in the admin. Both are free. Listing on the App Store needs a one-time $19 Partner registration.
If you'd rather not run infrastructure for a prototype, Gadget is a hosted full-stack platform with the Shopify connection, webhooks and data sync built in. The Hobby plan is free for 5 installs and Pro is $35 a month. The trade-off: bring-your-own-cloud is Enterprise-only, so plan the exit if the app takes off. For when a custom build beats both, see custom Shopify app development and checkout UI extensions.
§ 02The economics: the 0% revenue share
Shopify takes 0% of the first $1M of gross app revenue, counted over the app's lifetime from 1 January 2025, then 15%, plus a 2.9% processing fee. Many older posts still say "$1M per year". It's lifetime now, so it doesn't reset. It's still the best distribution deal in SaaS for a new app, but it doesn't bring installs by itself.
§ 03Find the stores: Store Leads and BuiltWith
Your best first merchants already pay for a competitor's app, or run the theme or stack your app improves.
- Store Leads indexes about 14.2M active stores along with their installed apps, from $75 a month. It's the cheapest way to filter "Shopify stores using app X in the US". It returns phone numbers and generic company emails, not people.
- BuiltWith covers more technologies, from $295 a month, which is better for agencies than for solo app founders.
§ 04Find the owner: SocLeads and Apollo
A store list without the owner's contact goes nowhere. Two routes:
- SocLeads pulls contacts from where small merchants actually live: Google Maps listings, Instagram, Facebook, TikTok, LinkedIn, X and YouTube. Its validator checks the emails. That's useful because DTC brands often publish an Instagram handle long before a decision-maker's LinkedIn. The free trial covers 100 contacts a month, Basic is $29 for 2,000 contacts and Pro is $59 for 10,000. It bills per row and a row may not include an email, so budget for that.
- Apollo.io is stronger for larger merchants with real org charts (heads of ecommerce, CTOs). It has a free plan, and paid plans start at $49 a month.
§ 05Send: Instantly
Instantly handles sending, inbox rotation and warm-up, from $47 a month (1,000 contacts and 5,000 emails). Send from a separate domain, never the one your app's transactional email uses. Keep each message to one store-specific observation and one offer: free setup for the first 20 merchants in exchange for a review.
§ 06Turn the first merchants into a listing that ranks
The first merchants' job is to produce:
- reviews that get the listing ranked in App Store search;
- case numbers for the listing ("+12% AOV on checkout");
- feature requests that show what to build next.
Ship those requests fast. A merchant who sees their idea live in a week writes the review without being asked.
§ 07When to build custom
Off-the-shelf builders get you to a prototype. A public app with real traffic needs:
- a backend you control;
- rate-limit-safe sync with the Admin API;
- checkout UI extensions that pass review;
- billing via the Shopify Billing API.
That's the work we do at Invental: see our custom Shopify app case study. Get in touch when the prototype has merchants waiting.