Shopify app development · San Francisco, California
Shopify App Development Agency in San Francisco, California
Aqsa Shahzad is a Shopify app development agency working with San Francisco merchants who have run out of road with off the shelf apps. We build the private apps, checkout logic and admin tools that your business needs but the App Store has never sold. Every project starts with one workflow you want gone. We scope it, engineer it on Shopify’s current APIs, and hand you the repository at launch.
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5.0 on Shopify Partners · Premier Verified on Clutch
Who this is for
Signs your California store needs a custom app
- 01
Gap
No app in the store does it
You've tried four apps and stitched them together. The workflow your business actually runs on still doesn't exist.
- 02
Checkout
Checkout logic won't bend
Custom discounts, bundle rules, shipping logic or payment gating that only Shopify Functions can enforce properly.
- 03
Operations
Your team is the integration
Someone re-keys orders into an ERP, a 3PL portal or a POS system every morning. That's an app, not a job.
- 04
App bloat
Ten apps, one slow store
Subscription fees stack up and every app injects scripts. One purpose-built app replaces the stack and the drag.
- 05
Founders
You're launching a saas app
You have the idea and the merchants. You need an engineering team that has passed App Store review before.
- 06
Legacy
Your app is on old apis
REST endpoints, deprecated script tags and unversioned webhooks. It needs migrating before Shopify forces the issue.
What’s included
Shopify app development solutions we offer in California
Every app is scoped around the workflow it replaces, not a fixed package. Here’s the full range of what we build for California merchants and app founders. Need the storefront engineered too? See our Shopify Plus development service.
- 01
Custom Shopify app development
Uptime monitoring, API version upgrades, webhook reliability and fixes long after launch day.
- 02
Public app development & app store launch
Shopify Billing API, usage charges, trials and plan gating implemented correctly the first time.
- 03
Shopify functions development
POS UI extensions and inventory logic for California retailers running several stores alongside online.
- 04
Checkout & admin ui extensions
Native surfaces inside checkout, the order status page and the Shopify admin — no iframe workarounds.
- 05
ERP, CRM & 3PL Integrations
NetSuite, SAP, Salesforce, HubSpot and fulfillment systems connected through a real middleware layer.
- 06
App migration & API upgrades
REST to GraphQL, script tags to extensions, and version pinning so a Shopify release never breaks you.
- 07
Headless & storefront API apps
Hydrogen, Oxygen and custom frontends backed by apps that serve data at storefront speed.
- 08
Pos & multi-location apps
POS UI extensions and inventory logic for California retailers running several stores alongside online.
- 09
Billing, plans & subscription logic
Shopify Billing API, usage charges, trials and plan gating implemented correctly the first time.
- 10
App maintenance, monitoring & support
Uptime monitoring, API version upgrades, webhook reliability and fixes long after launch day.
Public app development · california
From idea to app store listing
- Review-Ready
- Multi-Tenant
- Fixed Scope
We build production Shopify apps end to end, OAuth and session handling, GraphQL Admin API, webhooks with retries, Polaris admin UI on Remix, and Billing API plans. Written to Built for Shopify standards so review is a formality rather than a rewrite.
- 60+
- Apps Shipped
- 6 wks
- Avg. MVP Launch
- $25K+
- Typical Build
Shopify
Remix
React
Next.js
Storefront API
TypeScript
Any platform, one destination
Seamless migration to Shopify: your California store's next destination
- Admin
- POS
- Checkout
- Customer Accounts
An app is rarely one screen. Yours may need an embedded admin page, a Function running at checkout, a POS tile for your San Francisco store, a Flow trigger for the ops team, and a Storefront API feed for a headless front end. We build all of them against the same codebase and the same data model.
- 2026-07
- API Version We Ship On
- 100%
- Extension-Based
React
Next.js
Storefront API
TypeScript
GitHub
Vercel
Why Aqsa
Why California brands choose us for development
Here’s what changes when an app is engineered by people who ship on Shopify every week instead of general contractors learning the platform on your budget.Here’s what changes when a store is engineered for scale instead of assembled from off-the-shelf pieces.
- 01
Specialist
Shopify-only engineers
We work exclusively inside the Shopify ecosystem, so API limits, extension targets and review requirements are known constraints rather than discoveries.
- 02
Standards
Built for Shopify standards
Performance budgets, embedded App Bridge navigation, Polaris patterns and accessibility handled from the first commit, not retrofitted before review.
- 03
Ownership
You own the code
Your repository, your infrastructure, documented handover. No black boxes and no dependency on us to keep the app running.
How we work
Our Shopify App Development Process
A six-step system that takes a store from audit to launch with nothing left to guesswork, so you always know what’s next and why.
Discovery and technical feasibility
We map the workflow the app replaces and confirm what Shopify's APIs actually allow — rate limits, extension targets, data access. You get a written yes, no, or workaround before anyone estimates.
Week 1Architecture and scope
Data model, extension points, hosting, auth and billing decided up front. This roadmap fixes the scope and the number so the build stays predictable.
Week 1–2Interface design in Polaris
Admin screens designed with Shopify's own design system so the app feels native to merchants on day one — and passes the embedded experience requirements without rework..
Week 2–7App development
OAuth, GraphQL Admin API, webhooks with retry handling, Functions and UI extensions built on the current API version, with staging installs you can test in a real development store..
Week 6–7Testing, security and review prep
Load and edge-case testing, GDPR webhooks, scope minimisation, and a full pass against App Store requirements before submission rather than after rejection
Week 7–8Launch and ongoing support
We ship with monitoring and error tracking in place, then stay on for API version upgrades, fixes and new features — sized for peak season so the app holds when demand arrives.
Week 8+Proof
Real builds. Verified numbers.
Every number here is verified with the brand it belongs to.
- 01Read the case study
Gene Juarez
- Case study
The Zenoti booking integration most agencies declined — retail and salon booking unified on Shopify Plus.
- 02Read the case study
GetKif
- Case study
Figma to fully custom Shopify theme: pixel-perfect, fast, and editable end-to-end from the Theme Customizer.
Where we work
Shopify app development across California
We work remotely with California merchants and software teams, in Pacific Time, and travel for kickoffs and launch weeks. Most engagements run with teams in these markets.
- 01
Los Angeles
Fashion, beauty & entertainment
- 02
San Francisco
Tech & premium DTC
- 03
San Diego
Lifestyle, outdoor & wellness
- 04
Sacramento
Government, agriculture & retail
recent work
Case studies from real Shopify Plus builds.
A snapshot of stores we’ve shipped. Every number here is verified and client-approved.
Coco Lash
True Glory Hair
Cooney's Home Interiors
Gene Juarez
OuchieCap
GetKif
Frequently asked questions.
Do you work with San Francisco businesses remotely or on site?
Both. Day-to-day delivery is remote with a shared Slack channel and weekly demos, and we work in Pacific Time for your team's hours. We travel to San Francisco for kickoff workshops and launch weeks when the project warrants it.
What's the difference between a custom app and a public app?
A custom app is built and installed for one store — it never goes through App Store review, so it can do exactly what your business needs. A public app is multi-tenant, listed in the Shopify App Store, and sold to many merchants. We build both, and the choice usually comes down to whether you're solving your own problem or selling a product.
How much does Shopify app development cost?
Focused custom apps and integrations typically start around $15K. A public app built for App Store launch, with billing, onboarding and multi-tenant infrastructure, usually starts around $25K and scales with complexity. You get a fixed scope and a fixed number before any work starts — no hourly drift.
How long does it take to build a Shopify app?
Six weeks is our average from kickoff to first install for an MVP. Integrations with ERP systems, complex Functions logic or heavy data migration extend that, and we tell you which category you're in during the scoping call rather than after signing.
Do I need Shopify Plus to use a custom app?
No. Custom apps, the Admin API and most extensions work on standard Shopify plans. Plus is what unlocks certain checkout capabilities, higher API limits and B2B objects — so it matters for some app requirements and not for others. We flag that during feasibility so you're not upgrading for no reason
Can an app replace the Shopify apps I'm already paying for?
Often, yes. When a store is paying several monthly subscriptions for overlapping features — and taking the performance hit from each one's scripts — a single purpose-built app usually pays for itself within a year while removing the bloat.
Can you build checkout logic with Shopify Functions?
Yes. Discounts, shipping rules, payment method gating, cart transforms and validation run as Functions on Shopify's infrastructure — the supported replacement for Checkout Scripts, and far more reliable at volume.
Will you handle App Store submission and review?
Yes. We prepare the listing assets, complete the requirements checklist, run the security and performance passes, and handle reviewer feedback until the app is approved. We build to those standards throughout, so review is usually a formality rather than a rewrite.
Who owns the code and the infrastructure?
You do. The repository, the hosting accounts and the Shopify Partner app entry are yours from day one, with a documented handover at launch. You can take the app to any team afterwards.
What ongoing maintenance does a Shopify app need?
Shopify releases a new API version quarterly and deprecates older ones, so apps need periodic upgrades along with webhook monitoring, error tracking and dependency updates. We cover that on a retainer with the same engineers who built the app.
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Shopify Plus experts
Let's talk Shopify, Shopify Plus and the store you actually want.
An accredited Shopify Plus agency that designs, builds, migrates, supports and grows stores for brands that have outgrown templates. Ready when you are: talk to an engineer about the project.
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