Shopify App Development Company

Shopify Functions are WebAssembly (Wasm) modules that execute within Shopify's infrastructure to customize checkout and order management business logic. Functions receive a structured JSON input - cart contents, customer information, shipping context - and return a structured output - discounts to apply, shipping rates to show, cart validation results, or payment methods to customize. Functions are compiled to WebAssembly for sub-5ms execution performance and run in a sandboxed environment with specific input/output contracts defined by Shopify's Function APIs. Functions are written in JavaScript/TypeScript (compiled to Wasm) or Rust, and replace the deprecated ScriptTag approach for checkout customization. Available Function types include: Discount Functions, Shipping Customization Functions, Cart Transformation Functions, Cart and Checkout Validation Functions, and Payment Customization Functions.

Shopify Functions and Checkout Extensions solve different problems and are often used together. Functions handle business logic with no UI - they calculate discounts, filter shipping rates, validate carts, and transform order data. They execute server-side inside Shopify's infrastructure. Checkout Extensions add UI components to the checkout interface - upsell widgets, custom form fields, trust badges, loyalty point displays - using React components that render within Shopify's checkout sandbox. A complete checkout customization often uses both: a Function to calculate a discount and an Extension to display a UI prompting the merchant to use that discount. Both are required for Shopify Plus and standard stores - the deprecated checkout.liquid approach is no longer supported for new apps.

The Shopify Billing API handles all subscription management and payment collection for public apps. When a merchant installs an app, the app creates a subscription plan via the Billing API GraphQL mutation, which returns a confirmation URL. The merchant is redirected to this URL to approve the charge within their Shopify Admin. Once approved, Shopify automatically charges the merchant's payment method on each billing cycle (monthly or annually). The app receives webhook events for subscription creation, cancellation, billing attempts, and plan changes. Usage-based billing (charging per transaction or per API call) is also supported through usage charges with a capped maximum. Trial periods (7-30 days free before billing begins) are configured as part of the subscription plan definition.

To list a public app on the Shopify App Store, your app must pass Shopify's review process covering: (1) Functionality - the app works as described, all features function correctly, and the app value is demonstrable. (2) Security - OAuth 2.0 authentication is implemented correctly, API keys are not exposed client-side, HTTPS is enforced. (3) GDPR compliance - the three GDPR webhooks (customers/data_request, customers/redact, shop/redact) are implemented and respond with 200 status within 5 seconds. (4) UI compliance - the embedded Admin UI uses Polaris components correctly and follows Shopify's design guidelines. (5) Clean uninstall - webhooks are deregistered and any pending billing is cancelled on uninstall. (6) Legal - privacy policy and terms of service pages are provided. Evolution Infosystem conducts an internal App Store review checklist before every submission, achieving 100% first-pass approval rate.

A simple Shopify public app with Admin UI, webhook integration, and basic Billing API takes 6-10 weeks. A medium-complexity app with Shopify Functions, Checkout Extensions, multi-tier billing, and third-party integrations takes 3-5 months. A complex multi-feature app targeting significant App Store volume takes 5-8 months. App Store review typically takes 3-10 business days after submission. Timeline depends on feature scope, number of Shopify APIs integrated, backend complexity, and the number of review/revision cycles. At Evolution Infosystem, we deliver working app builds on Shopify development stores every 2 weeks throughout the project.

App Bridge is Shopify's JavaScript library that creates the embedded app experience within Shopify Admin. When a merchant manages your app from their Shopify Admin dashboard, your app renders inside an iframe within the Shopify Admin interface. App Bridge handles the authentication token exchange between Shopify and your app, enables navigation that works within the Admin's frame, provides access to Admin-authenticated API calls, and gives your app access to Shopify Admin features like modals, toasts, and context bars. All public apps that embed in Shopify Admin (which is the vast majority) must use App Bridge 3 - the current version. Apps using deprecated App Bridge 1 or 2 will fail Shopify's review process and may show security warnings to merchants.

Yes. Shopify App Store listing optimization is a distinct discipline from Google SEO - the App Store has its own search algorithm based on app name, description keywords, install count, review rating, and merchant engagement signals. We provide keyword research for Shopify App Store search terms, competitive analysis of top-ranking apps in your category, listing copywriting with problem/solution framing and compelling feature descriptions, screenshot design following Shopify's specification (1600×900px with clear feature captions), feature video production guidance, and a review acquisition strategy for launching with social proof. A well-optimized App Store listing can generate significant organic installs at zero cost-per-install - making it one of the highest-ROI investments for a new Shopify app.

Shopify public app development, Shopify Functions (Discount, Shipping, Cart Validation), Checkout UI Extensions, Admin UI Extensions, Billing API integration, App Store listing optimization, Shopify private app development, and legacy app migration to CLI 3.

Yes. Evolution Infosystem is a certified Shopify Partner with access to unlimited Shopify development stores, Partner Dashboard, and Shopify's partner resources for building and managing public apps.

100% first-pass App Store review approval rate across all Shopify app submissions - achieved through a systematic internal App Store review checklist covering GDPR webhooks, OAuth security, Polaris UI compliance, and clean uninstall requirements.

Yes. Evolution Infosystem builds all Shopify Function types - Discount Functions, Shipping Customization Functions, Cart Validation Functions, Cart Transformation Functions, and Payment Customization Functions - in JavaScript/TypeScript and Rust.

Yes. Evolution Infosystem designs and implements complete Shopify app monetization including recurring subscription plans, usage-based billing, tiered pricing, trial period management, and billing webhook handling.