Available for remote freelance work

The Mobile
Fullstack
Developer.

I'm Nik — a Mobile Fullstack Developer, expert in the whole stack behind an app: native iOS with Swift/SwiftUI, Flutter for cross-platform, and the Node.js/Firebase backend that powers it. Most of my recent work is fintech and health apps — payment gateways, Apple Pay, secure data handling — including contributions to Credit Karma and ConfirmTkt. If you need one person who can take your app from API to App Store, that's what I do.

30+
CLIENTS SERVED
50+
APPS SHIPPED
100M+
USERS ON MY APPS
4+
YEARS, ONE CLIENT
MY OWN APP
Inflixo AI
A streaming app for content creators — I built this one on my own, start to finish
Credit KarmaFintech · 50M+ installs
ConfirmTktTravel · 100M+ installs
Time Clock WizardSaaS · 4+ yr client
Aura SecuritySecurity · Top rated
4+
yrs with TCW
TECH STACK

The full stack, not just the app

"Mobile Fullstack" means I don't stop at the UI. I write the iOS/Flutter app, the backend it talks to, and wire up the third-party services in between.

Languages
SwiftDartKotlinObjective-CJavaScriptJava
Mobile
SwiftUIUIKitFlutterReact NativeIonicRiverpodBloc
Backend
Node.jsREST APIsFirebase FunctionsExpress
Databases
FirebaseMongoDBMySQLCore Data
Payments & Fintech
Apple PayStripeRazorpayGoogle PayCard Tokenization
Apple Frameworks
HealthKitAVFoundationCore MLCoreLocationMapKit
AI Integration
OpenAI APIGPT-4Prompt EngineeringCore ML
Cloud & Tools
GitFastlaneTestFlightApp Store ConnectFirebase Console
SERVICES

What I can take off your hands

I've been doing freelance and remote contract work for the last 3 years, with enough hands-on experience behind me to know what actually ships. Here's what clients usually hire me for.

iOS App Development

Native apps built with Swift and SwiftUI — a new app from scratch, or new features added to one you already have.

  • New app builds
  • Feature additions to existing apps
  • App Store submission

Flutter Cross-Platform Apps

One codebase, both platforms. Good fit for MVPs and budgets that need iOS and Android together.

  • MVP builds
  • Native-to-Flutter migration
  • Ongoing feature work

Payments & Fintech Integration

Apple Pay, Stripe, Razorpay, recurring billing, card tokenization — built carefully because money is involved.

  • Payment gateway SDKs
  • Subscription / recurring billing
  • Secure card entry flows

Backend & API Development

The Node.js / Firebase backend your app needs to actually work — not just the screens.

  • REST API design & build
  • Firebase setup & security rules
  • Database architecture

App Store Launch & Maintenance

Submissions, crash fixes, OS updates — someone to keep your app running after it's live.

  • App Store / Play Store submission
  • Bug fixes & OS updates
  • Long-term maintenance contracts

MVP & Technical Consulting

Not sure whether to go native or Flutter, or how to scope your build? I'll give you a straight answer before you spend money.

  • Native vs. Flutter decisions
  • Architecture & code review
  • Scoping & timeline estimates
WHY WORK WITH ME

What you get when you hire me

You're not hiring an agency where your project gets passed around. You talk to me directly, and I write the code myself.

One person, no handoffs

I'm the developer you talk to and the one who writes your code. No project manager in between, no junior dev learning on your project.

Real experience with money & health apps

I've worked on apps that handle real transactions and real user data — Credit Karma, payment gateways, security apps. I know what "handle it carefully" actually means in code.

4+ years with the same client

My longest client relationship is over 4 years. Clients keep me because I show up, meet deadlines, and don't disappear after the first bug.

Clear communication

I give you regular updates, I flag problems early instead of at the deadline, and I explain things in plain language, not just technical jargon.

Both iOS and Flutter

Native iOS with Swift, or one Flutter codebase for iOS and Android both. I'll tell you honestly which one fits your budget and timeline.

I can take your requirements as they are

Send me your spec, your Figma file, or even just a rough idea — I'll tell you clearly what's possible, what will take time, and what it will cost before we start.

NM
50+
Apps delivered
Ahmedabad, India
ABOUT ME

My background

I'm Nik, a mobile app developer based in Ahmedabad, India. I've been writing code long enough to know what actually ships, and for the last 3 years I've worked as an independent freelancer, taking on remote contracts directly with companies instead of going through an agency.

I currently work as the only mobile developer for Eviid, a UK-based company, and I've had a 4+ year partnership with US-based SaaS company Time Clock Wizard. I've also contributed to apps used by tens of millions of people, including Credit Karma and ConfirmTkt.

Outside client work, I built Inflixo AI, a streaming app for content creators, completely on my own — design, code and launch. It's how I learned to think about a product as a whole, not just the part I'm assigned to build.

IBM AI & Machine Learning
Professional Certificate · 2023
Apple iOS & Flutter
Certified Developer · 2020
B.E. Computer Science
GTU · 2009–2013
Inflixo AI — Founder
Built & launched solo · 2024
SKILLS

What I work with

Native iOS, cross-platform apps, payments, and the backend to connect it all.

01
iOS development
Apps built with Apple's current tools, ready for the App Store.
SwiftSwiftUIUIKitObjective-C
02
Flutter & cross-platform
One codebase for iOS and Android. Used on apps with 100M+ downloads.
FlutterDartReact NativeIonic
03
Payments
Apple Pay, subscriptions, card entry — built carefully because money is involved.
Apple PayStripeRazorpayGoogle Pay
04
Health & security apps
Apps that handle personal data — same careful approach as payments.
Biometric AuthHealthKitEncryption
05
Android & backend
Native Android, plus the backend and APIs to connect your app to everything else.
KotlinNode.jsFirebaseMongoDB
06
AI features
Real features built on OpenAI's models — actual product use, not just a demo.
OpenAI APIGPT-4CoreML
MY WORK

Top 10 projects

For each one below: what I built, what I was responsible for, and the hard part I had to solve. I've shipped 24 apps in total — the rest are further down if you want to see everything.

LIVE RIGHT NOW, ON THE APP STORE & PLAY STORE
Credit Karma
Fintech
iOS
ConfirmTkt
Travel
Android
Time Clock Wizard
SaaS
iOSAndroid
Aura Security
Health & Security
iOS
Crowdfire
Social
iOSAndroid
Inflixo AI
OTT — my own app
Web
01
CK
Credit Karma
Credit monitoring and financial insights app used across the US.
Fintech
MY ROLE

Worked as part of the iOS team, building and maintaining screens used by tens of millions of people.

WHAT I BUILT
  • Credit score and report screens
  • Real-time alerts for account changes
  • Identity protection features
THE CHALLENGE

The app deals with sensitive financial data at huge scale — every screen had to be fast, accurate, and tested carefully before release.

02
CT
ConfirmTkt
India's #1 train booking app, IRCTC-authorised partner.
Travel
MY ROLE

Android developer on the team, working on booking and tracking features used by over 100M people.

WHAT I BUILT
  • Waitlist prediction display
  • Live train tracking
  • Booking flow improvements
THE CHALLENGE

Millions of people check this app daily during peak booking season — it has to stay fast and accurate under heavy load.

03
TCW
Time Clock Wizard
US SaaS platform for employee time tracking and payroll.
SaaS · 4+ yrs
MY ROLE

Ongoing developer for over 4 years — the app is mine to maintain and grow across iOS and Android.

WHAT I BUILT
  • GPS-based clock-in / clock-out
  • Payroll and shift reports
  • Shift management tools
THE CHALLENGE

A long-running app means constant updates without breaking things businesses depend on every day for payroll.

04
AS
Aura Security
Top-rated iOS identity protection app.
Security
MY ROLE

iOS developer building the monitoring and alerts side of the app.

WHAT I BUILT
  • Real-time threat monitoring
  • Data-breach alert system
  • Account protection settings
THE CHALLENGE

Alerts need to reach users the moment something happens, without false alarms that make people ignore them.

05
CF
Crowdfire
Social media management app used by millions of creators.
Social
MY ROLE

Flutter developer working on content scheduling and analytics screens.

WHAT I BUILT
  • Content scheduling calendar
  • Analytics dashboards
  • Multi-platform post publishing
THE CHALLENGE

Connecting to several social platforms at once, each with different rules and rate limits, without the app feeling slow.

06
LD
LoanDepot Mobile
Mortgage management app for US homebuyers.
Fintech
MY ROLE

iOS developer for the loan tracking and document features.

WHAT I BUILT
  • Loan status tracking
  • Document upload and management
  • Payment schedule view
THE CHALLENGE

Mortgage data has to be shown clearly and correctly — no room for a number being wrong.

07
PR
PayRemit
International money transfer and remittance app.
Fintech
MY ROLE

Flutter developer building the transfer flow and transaction history.

WHAT I BUILT
  • Cross-border transfer flow
  • Currency conversion display
  • Transaction history & receipts
THE CHALLENGE

Money moving between countries means handling delays, failures, and retries without confusing the user about where their money is.

08
MW
Multi Wallet
Cryptocurrency wallet with multi-currency support.
Crypto
MY ROLE

Flutter developer for the wallet and portfolio tracking screens.

WHAT I BUILT
  • Multi-currency wallet view
  • Real-time portfolio tracking
  • Secure transaction signing
THE CHALLENGE

Crypto wallets have zero tolerance for bugs — a mistake here means someone actually loses money.

09
WB
Wa Bank
Mobile banking app with real-time account management.
Banking
MY ROLE

Flutter developer on account management and login security.

WHAT I BUILT
  • Account balance & transaction history
  • Biometric login
  • Account management screens
THE CHALLENGE

Banking apps get audited — the login and data-handling code has to hold up to real security review.

10
GC
Green Clippings
Health and wellness content app.
Health
MY ROLE

iOS developer building the content feed and personalisation.

WHAT I BUILT
  • Curated content feed
  • Personalised recommendations
  • Save & reading-list features
THE CHALLENGE

Health content needs to feel trustworthy — the app had to load fast and stay simple, not cluttered.

EL
Finance

Easy Life Finance

Personal budgeting and expense tracking app.

MC
Finance

Mortgage Calculator

Mortgage calculation and financial planning tool.

SL
Social

Sober Love

Dating app for sober individuals with identity verification.

SM
Messaging

Sense Messaging

End-to-end encrypted messaging app.

GB
Social

Glambu

Social dating app with profile matching and chat.

YB
Education

Yap Books

Voice-enabled interactive books app for kids.

JG
Gaming

Jovial Gaming

Multi-game app with leaderboards and rewards.

RC
Comics

River Comics

Digital comic reader with offline reading.

DG
Gaming

Delta Game Emulator

Featured App Store game emulator with save states.

FC
Sports

My Football Career

Football career simulation game.

PR2
PropTech

Proud Residence

Society management app with maintenance requests.

LV
Streaming

Live Ventania

Real-time live streaming app with WebRTC.

LP
Travel

Live Porto

Tourist guide with live content and maps.

LJ
Travel

Live Jeri

Local travel guide with live streaming.

HOW I WORK

How a project runs

Simple and predictable — you always know what's happening next.

STEP 01

Understand the requirement

I read your spec or talk to you directly, and make sure I understand what you actually need before quoting anything.

STEP 02

Plan and quote

I break the work into milestones with a timeline and price, so there are no surprises later.

STEP 03

Build with updates

I share progress regularly and flag any issue as soon as I find it, not at the deadline.

STEP 04

Deliver and support

Tested, App Store-ready code, plus support after launch if something needs fixing.

CLIENT REVIEWS

What clients say

Feedback from clients across the US, Europe and Asia over 9+ years of work.

★★★★★

Nick is an outstanding iOS developer. He delivered a clean, fast, and reliable app. We're thrilled with the results and look forward to future collaborations.

NK
Nick Kneuper
BestSelf Ventures, LLC
★★★★★

Nick was a key contributor, delivering high-quality work on time. His insights greatly improved our product. I look forward to working with him again.

SC
Sam Crigman
Procore Technologies
★★★★★

Nick delivered excellent work within budget and on time. His communication and documentation were top-notch. I look forward to future projects together.

BL
Bobby Leach
CenterPunch
★★★★★

Nick is the best developer I've worked with. His work is flawless and delivered quickly. I highly recommend him for any project without hesitation.

AG
Ayité Gaba
TOGO TIMBER S.A.
★★★★★

Nick is the best developer on Upwork. His work is professional and without error. He works quickly and always updates his skill set. Highly recommended.

SM
Seun Moses
Verified Client
★★★★★

Nick is the best iOS developer I've worked with. He went above and beyond, adding features that genuinely improved the app. Highly recommend.

JP
John Porrini
TheMobileAppGuys
★★★★★

Nick has been a reliable developer, always available when needed. His ongoing support has been invaluable. I highly recommend him for long-term projects.

DC
DomiNick Curatola
Long-term Client
★★★★★

Nick's understanding of iOS development is exceptional. One of the best developers I've worked with on Upwork — always delivers on point.

EJ
Eli Jacobson
Verified Client
★★★★★

Nick's professionalism and quality of work are unmatched. He delivers exactly what's promised and communicates clearly throughout the project.

MX
Mike Xhaxho
Verified Client
GET IN TOUCH

Let's talk about your project

Tell me what you're building and what you need. I'll reply honestly — if it's something I can do well, I'll tell you how. If it's not a good fit, I'll say that too. Usually reply within 4 hours.

LOCATION
Ahmedabad, India (Remote — available worldwide)
EMAIL
nikunj.cronative@gmail.com
PHONE / WHATSAPP
+91 87583 50987
MY OWN APP