One codebase, both stores
One Flutter app for iOS and Android, with native Swift or Kotlin where a plugin isn’t enough.
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Freelance Flutter developer · iOS & Android
A Flutter developer who gets your app paid on both stores.
I'm Sanjeev Singh, a freelance Flutter developer who started on native Android and Java in 2016. I built CRUD Review, live on the App Store and Google Play, with subscriptions and free trials through both stores’ billing. One Flutter codebase, native Swift or Kotlin where a plugin falls short. You get a fixed quote within 24 hours, and you own the code.
- Live app
- CRUD Review · 5.0 on Google Play
- Experience
- Mobile since 2016, Android and Java first
- Quote
- Fixed price, within 24 hours
01The usual problem
The app works in the demo. Then real users arrive, and the subscription says they never paid.
Sound familiar? Tick what applies to you.
02What you get
Subscriptions that stay in sync
Free trials, upgrades, restores and cancellations handled on both stores, with the server as the source of truth, not the phone.
- StoreKit 2
- Google Play Billing
- Server receipts
State that stays predictable
BLoC architecture, so every screen knows exactly what to show, and bugs are found in tests rather than by users.
- BLoC
- Clean modules
The backend too
The API, database and admin panel your app needs, so one person owns the whole system.
- Node.js
- PostgreSQL
- REST API
Through store review
Privacy labels, permissions, sign-in rules and subscription wording set up so the build passes Apple and Google review.
Native features
Camera, QR scanning and OTP login, tested on real iPhones and Android phones.
- Camera
- QR
- OTP login
03What changes
An app that works, and gets paid, on both stores.
- Live on the App Store and Google Play under your accounts
- Subscriptions that unlock the moment someone pays
- One codebase your next developer can read
- The developer who built it, one message away
04Overview
Why hire a freelance Flutter developer?
Flutter lets one codebase run on both iPhone and Android, so an app costs less to build and maintain than two native apps. Sanjeev Singh is a freelance Flutter developer who started on native Android and Java in 2016. He builds Flutter apps for iOS and Android, including the backend, subscriptions and store submission, and every project starts with a fixed written quote within 24 hours.
His main Flutter project is CRUD Review, an app live on the App Store and Google Play and rated 5.0 on Google Play. It has an owner console, a staff mode that logs in by scanning a QR code, OTP login and subscriptions with a 3-day free trial through both stores’ billing. The same backend serves a Next.js web app, so the business has one system across phone and browser.
Subscriptions and in-app purchases are where many Flutter apps fail. Common bugs include a paid user still seeing the paywall, Restore Purchases doing nothing on a new phone, and cancelled subscriptions unlocking premium for days. The fix is to make the server the source of truth: the backend checks receipts with Apple and Google and listens to App Store Server Notifications and Google Play Real-time Developer Notifications. Sanjeev builds subscriptions this way, on StoreKit 2 and Google Play Billing.
For structure, he uses BLoC state management, so each screen knows exactly what to show and bugs are caught in tests rather than by users. Where a plugin falls short, he writes the native part in Swift or Kotlin. Apps are tested on real iPhones and Android phones and set up to pass store review, with privacy details, permissions and subscription wording in order.
Typical work includes new Flutter apps from the first screen to both stores, fixing in-app purchases in existing apps, taking over apps another developer started, and resolving store rejections or crashing releases. The app is published under your own developer accounts, so the listing and its reviews belong to your business.
He works with clients in the UAE, Australia, the US and the UK. The timeline depends on the number of screens, the backend and the payments involved, and is written into the quote. Payment is in US dollars against milestones, each released after you have tested that stage on your own phone.
05Ways to work together
- 01
A new Flutter app
From the first screen to both stores, with its API and admin panel if you need them.
- 02
Subscriptions and in-app purchases
Trials, upgrades, restores and server receipt checks on StoreKit 2 and Google Play Billing.
- 03
Take over an existing app
An app someone else started, reviewed, fixed and moved forward, without a rewrite.
- 04
Store rejections and crashes
A rejected build or a crashing release, found, fixed and resubmitted.
06Proof
07In their words
Rated on Fiverr
5.0
23 reviewsRead them
Sanjeev has been instrumental across several projects. He understands the vision from very little direction, then brings commitment, technical skill and original thinking to turn it into a finished product.
Working with Sanjeev was a great experience.
Great job again.
01 / 03
08Your time, my time
Your time · Dubai
--:--
My time · Lucknow, India
--:--
Your office hours (9 AM–6 PM)When I'm on calls and chat
09Your options
Who builds it
Working with meMe, from the first screen to the stores
- An app agency
- A team, after sales hands over
- A marketplace gig
- Whoever wins the bid
In-app purchases
Working with meTested on both stores before launch
- An app agency
- Usually included
- A marketplace gig
- Often left half done
The backend
Working with meBuilt by the same person
- An app agency
- A separate team
- A marketplace gig
- Often not included
Who owns the code
Working with meYou, with every login, from day one
- An app agency
- Sometimes the agency
- A marketplace gig
- Depends on the seller
After launch
Working with meThe same person, one message away
- An app agency
- A support ticket queue
- A marketplace gig
- Ends when the gig closes
| Working with me | An app agency | A marketplace gig | |
|---|---|---|---|
| Who builds it | Me, from the first screen to the stores | A team, after sales hands over | Whoever wins the bid |
| In-app purchases | Tested on both stores before launch | Usually included | Often left half done |
| The backend | Built by the same person | A separate team | Often not included |
| Who owns the code | You, with every login, from day one | Sometimes the agency | Depends on the seller |
| After launch | The same person, one message away | A support ticket queue | Ends when the gig closes |
10Free guide
In-app subscriptions in Flutter: a checklist
Most subscription bugs come from the same few gaps. Check these before launch, whoever builds your app.
On the server
- The server decides who has paid. The app asks your backend, which checks the receipt with Apple or Google. Never trust a flag stored on the phone.
- Listen for store notifications. Apple’s App Store Server Notifications and Google’s Real-time Developer Notifications tell you about renewals, refunds and cancellations as they happen.
- Store the original transaction ID, so a restore on a new phone links back to the same customer.
In the app
- A working Restore Purchases button. Apple requires one, and users need it after changing phones.
- Refresh status when the app opens, not only at purchase time, so a cancellation shows up straight away.
- Handle pending payments. Some payment methods take time to clear, and the app should say so rather than fail.
Before store review
| Check | Why it matters |
|---|---|
| Price, length and trial shown before purchase | Both stores reject paywalls that hide the terms |
| Links to terms and privacy policy | Required on the subscription screen |
| Sandbox and test-track purchases tested | Catches broken flows before reviewers do |
| Account deletion inside the app | Apple requires it for apps with sign-up |
Building something new? Start with web app or mobile app.
11How we work
- 01
Discover
A short call on goals, audience and what success looks like.
- 02
Fixed quote
Scope, timeline and price agreed in writing before work starts.
- 03
Build
Working pages shared early on a staging link, refined with your feedback.
- 04
Launch
Go-live, speed and SEO checks, then handover. You own the code, domain and accounts.
12Questions
Is Flutter good enough for a production app?
Yes, for most business and consumer apps. CRUD Review runs on one Flutter codebase on iOS and Android. Where a plugin isn’t enough, I write the native part in Swift or Kotlin.
Can you fix in-app purchases or subscriptions in my existing app?
Yes. The usual causes are trusting the phone instead of the server, missing restore handling and not listening for renewals and cancellations. I trace the full purchase flow on both stores and fix it at the source.
Do you publish the app to the App Store and Google Play?
Yes, under your own developer accounts, so the app and its reviews belong to your business. I handle the store listings, privacy details and review submissions.
Do you build the backend as well?
Yes. I build the API, database and admin panel in Node.js and PostgreSQL, so one person owns the whole system.
How long does a Flutter app take?
It depends on the number of screens, the backend and the payments involved. The written quote gives your exact timeline, and you get test builds on your own phone along the way.
How do payments work?
I invoice in US dollars, wherever you are, against milestones agreed in the quote. You don’t pay for a stage until you’ve seen it working on your phone.
Who owns the app when it’s done?
You do. The code, the store listings, the developer accounts and every login are in your name.
Question not here? Ask me directly.
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