Appther is a mobile app development company in New York that builds custom iOS, Android and AI-powered apps for the firms that set the pace here: Wall Street desks, Midtown media groups, hospital systems and the retailers of Fifth Avenue. 200+ products shipped since 2018, a team on Eastern Time, and a fixed price before the first sprint.
Consult Our New York TeamTeams that ship with Appther
New York does not forgive a slow app. Our app developers in New York build for a trader who needs a fill confirmed before the elevator doors close, a nurse on a night shift at a Manhattan hospital, a shopper on a subway platform with one bar of signal, and a compliance officer who will actually read the audit log.
Native Swift and Kotlin apps, or one Flutter or React Native codebase for the App Store and Google Play
Fintech-grade builds: NYDFS cybersecurity rules, SEC and FINRA record-keeping, PCI DSS tokenization
Backends and APIs load-tested for the market open, the lunch rush and the holiday peak
NY SHIELD Act, HIPAA and NYC biometric rules handled in the architecture, not after the audit
Integration with trading, EHR, ad-tech, CRM and order-management systems
Research, design systems and release management for both stores
From a Flatiron startup shipping its first MVP to a Financial District firm replacing a decade-old client app, our app developers in New York cover the whole mobile stack. Pick the service that fits, or bring us the problem and we will recommend the platform.
Our iOS app development in New York is for products that have to clear App Review and a compliance desk in the same week: Swift and SwiftUI, with Core Data, Combine and Core ML where the product needs them, shipped through Fastlane and TestFlight, with Apple Business Manager for private distribution to traders, clinicians and field staff.
Android app development in New York with Kotlin and Jetpack Compose, tested on the mid-range devices that dominate the city's delivery, retail and healthcare workforces rather than the newest flagship. We handle Play Console policy, Play Integrity and background-work limits so the release is not the first time you hear about them.
One Dart codebase for iOS, Android and web, rendered at 60 frames per second with full control of the interface. Our Flutter developers reach for it when a New York business wants both stores on one budget and one release calendar.
Product teams already working in TypeScript get one team for web and mobile: React Native shares logic, components and engineers across surfaces. We build on the new architecture with Hermes, use Expo where it earns its place, and write native modules where it does not.
Apps for watchOS and Wear OS, and companion apps for connected hardware: patient monitors, building-access and HVAC controls, retail sensors and connected fitness equipment. Our IoT app development team builds the mobile layer together with the firmware and the cloud pipeline under it.
Most New York mobile products need a browser surface: a client portal, an admin console, a partner dashboard. We build them in React and Next.js against the same backend as the app, so custom software development in New York covers every screen the business uses.
Some products should not live in a store: event apps for a conference at the Javits Center, kiosk experiences, internal checklists, B2B ordering for restaurant suppliers. Our hybrid and PWA builds install from a link, work offline through service workers and send push where the browser allows.
Assistants, recommendations and computer vision added to the product you already run. Our AI development practice brings LLM features and predictive models into mobile apps with the data controls a New York compliance team will ask about.
Whether it serves clients in the Financial District, patients across a hospital network or shoppers on Fifth Avenue, an app in New York has to be fast, audit-ready and honest about what it does with data. Tell us what it has to do and we will reply with a platform recommendation and a scoped plan.
Start With a Free Scoping Call
Six products from our portfolio that map to what New York builds: mobility, money, media, medicine, education and retail support. Every metric is lifted from the published case study.
Lyftup needed three coordinated apps that dispatch intelligently, price transparently and hold up when demand spikes after an event lets out.
Smart dispatch, live tracking, in-app payments and an admin control center for fleet owners, sharing a single backend and data model.
Lyftup · Ride-hailingRecording an ECG takes minutes; getting a cardiologist to read it took days, and every step handled protected health information.
A patient iOS app for uploading tracings and symptoms, a clinician portal for reading and signing, and one HIPAA-grade backend with audit logging under both.
KALBI · TelecardiologyA fintech startup had to serve customers with no bank account and no card, in a market where cash still settles most transactions.
Wallet-to-wallet transfers in under three seconds, QR payments, an agent cash-in and cash-out network and an operations console, shipped in six languages.
Digital wallet · FintechA satellite TV service wanted to reach viewers on every device they own without rebuilding its content operation for each one.
OTT apps for mobile, web and connected TV with adaptive streaming and casting, plus a control center the broadcaster uses to manage channels everywhere at once.
Ideal TV · OTT streamingCourses, live classes, assessments and attendance lived in separate tools, and no administrator could see a student's whole picture.
One platform for course management, live classes, assignments, attendance and analytics, with a role-specific experience for students, faculty and administrators.
LMS · EducationOnline retailers were paying agents to answer the same order-status, returns and delivery questions thousands of times a week.
A conversational AI assistant on WhatsApp that reads order data, answers in context and hands the hard cases to a human with the history attached.
Support AI · Retail"Appther built our student competition app and portal exactly the way we envisioned it: easy registration, smooth judging workflows, and real-time results that keep participants engaged. Our coordinators no longer chase spreadsheets."
Dionna MilemOwner, My BOB Team LLC"Building a mental health app means every detail, tone, flow, and privacy, has to be handled with care, and Appther got that from day one. They translated a sensitive subject into a product that feels warm, simple, and genuinely helpful."
Bob SinghalProfessor of Joy, Joyscore Inc"Appther exceeded every expectation, on time, on budget, and the final product has been instrumental in scaling our business. A rare engineering partner."
Johnathan PefferCEO, Bull's Eye Technologies IncFinance and insurance, media and advertising, healthcare, real estate, retail and the public sector: New York's economy is five economies stacked on one island, each with its own regulator and its own idea of a good app. Our mobile app development company in New York builds around that sector's workflow, rules and user.
New York layers its own rules on top of the federal ones: the SHIELD Act for anyone holding a New Yorker's data, NYDFS cybersecurity regulation for financial licensees, the city's biometric identifier law for shops and venues, and a local human-rights law that treats an inaccessible app as discrimination. We settle all of it with your counsel before design starts.
A mobile app development company in New York is measured by the people who never see the app: the auditor, the compliance officer, the procurement analyst. Five reasons the relationship usually outlasts the first release.
Trading platforms, wallets, clinical apps and insurance workflows are on our record. We know what NYDFS, a PCI assessor and a HIPAA audit will ask, and we design so the answers already exist.
New York firms run on systems older than the app store. We connect mobile products to order-management systems, EHRs, policy platforms and custom ledgers through secure APIs, so the app joins the workflow instead of duplicating it.
We test on mid-range devices, throttled networks and offline mode, because the app has to work on the L train between stations and in a hospital basement, and New Yorkers delete anything that makes them wait.
You get a fixed price at the end of discovery, a scope that does not drift, and a named senior engineer on Eastern Time who demos working software every other week. Nobody sends a surprise invoice.
Trades executed, appointments booked, orders per hour, claims closed. We agree the metric in week one, report on it after launch, and say when a requested feature will not move it.
Assistants, recommendations and predictive alerts, scoped to a business outcome and shipped inside the product you already have, with the data controls a New York compliance team expects. Teams use us for:
New York projects rarely fail on features. They stall on a security review that arrives after the build, a legacy system nobody wants to touch, a launch that folds under the morning rush, and users who never come back for a second session.
The app is finished, then information security sends a 200-question vendor assessment, legal asks about NYDFS Part 500, and the launch slips a quarter.
We answer the questionnaire before the build by designing to it: MFA, encryption, logging, access reviews and a written runbook, documented as we go so the assessment is a formality.
SecurityThe order-management system, the EHR or the policy platform predates smartphones, and every integration attempt so far has been slow, fragile and expensive.
A secure integration layer of APIs, middleware and event streams sits between the app and the system of record, so the old platform stays where it is and the app gets live data.
IntegrationTraffic in New York arrives all at once: the market open, the lunch order, the 5 p.m. commute. Apps sized for the average hour fall over in the peak one.
Stateless services, queues, caching and autoscaling, load-tested against the peak rather than the mean, with graceful degradation when a dependency slows down.
ScaleMost apps lose most of their users inside a month, because the second session offers nothing the first one did not.
Onboarding, notifications and personalization built around one retention number, instrumented from day one and tuned on live data after launch.
RetentionWe add these where they change an outcome for the client, the patient or the business, and leave them out where they would only add cost and review time. Every card links to the practice that delivers it.
Risk scoring, personalization and forecasting models trained on your own data, built for the scrutiny a New York model-risk or compliance team will apply.
Client, patient and employee assistants that answer only from approved documents and policies, with sources attached and every response logged.
Building systems, patient monitors, retail sensors and connected equipment surfaced in a mobile app that facilities and clinical teams actually open.
Trading, claims, occupancy and order data turned into dashboards a New York operator can act on before lunch, not in next month's export.
Voice agents that answer patient, tenant and customer calls around the clock, book appointments and resolve routine requests on the same backend as the app.
Tokenized assets, settlement records and wallet integrations for products where provenance or ownership has to be provable to a regulator.
Picked for staying power rather than novelty. Every tool below has cleared an enterprise security review, has a deep hiring market in New York, and will still be maintained when your app is five years old.
Swift
SwiftUI & UIKit
Xcode
iOS SDK
Kotlin
Jetpack Compose
Android Studio
Android SDK
Flutter
Dart
React Native
Expo
Ionic
Node.js
NestJS
Python
Django
FastAPI
Laravel
Go
PostgreSQL
MongoDB
MySQL
Redis
Firestore
SQLite
Supabase
AWS
Microsoft Azure
Google Cloud
Docker
Kubernetes
Terraform
Auth0
Okta
Keycloak
Firebase Auth
Face ID & Biometrics
OAuth 2.0 / OIDC
Firebase Cloud Messaging
Apple Push Notification service
OneSignal
Twilio SMS & WhatsApp
Stripe
Braintree
PayPal
Square
Apple Pay
Google Pay
Plaid & ACH
Google Analytics 4
Mixpanel
Sentry
Datadog
Grafana
Crashlytics
GitHub Actions
GitLab CI
Fastlane
Bitrise
Jenkins
TestFlight
Send us the idea and we will return a scoped estimate with the platform, team and timeline behind the number, usually within one business day, and without Manhattan agency overhead.
Get a Scoped Estimate
Six stages, each ending in something you can open, click or sign. Audit-ready from the first sprint, fixed-price from the first invoice.
We start with the business need and the number it must move, then map the regulatory surface: SHIELD Act and HIPAA for data, NYDFS and SEC rules for financial products, the city's biometric and accessibility laws for consumer apps. You leave with a written scope and a fixed price.
Timeline, team, integrations and release plan agreed in writing, including the security documentation your vendor-risk team will want. We plan around your calendar, so a trading feature is not landing on a quarter-end and a retail app is not launching the week before Black Friday.
Our app developers in New York design for the person actually holding the phone: a broker between calls, a nurse on a night shift, a courier at a loading dock. Wireframes, clickable prototypes and a design system are tested with real users before production code.
Two-week sprints, each closing with a demo of working software. Native Swift and Kotlin where the product needs it, Flutter or React Native where one codebase is the smarter spend. Backend, API and integration work runs alongside the app so the schedule has no idle weeks.
Real devices, throttled networks and offline mode, plus security testing against OWASP MASVS and accessibility checks against WCAG 2.2 and the NYC Human Rights Law. Nothing ships with an open critical.
App Store and Google Play submission, release monitoring and the first weeks of hypercare, then an SLA-backed support plan with crash, performance and retention dashboards you can read without us.
Mobile app development cost in New York depends on scope, platform, design complexity, the backend and integrations behind the app, and advanced features such as trading, payments, AI or biometrics. Regulated products carry extra security and documentation work, and we price that line by line instead of burying it.
Need a real figure? Talk to our team for a fixed-price quote on your New York app, with no open-ended billing after discovery.
A focused MVP takes 8 to 14 weeks from kickoff to store submission. A mid-scale product with a custom backend and third-party integrations takes 3 to 6 months. Enterprise builds with security reviews, multiple user roles and legacy integrations usually run past 6 months, and the vendor-assessment cycle at a large New York firm can add weeks on its own, which is why we start that paperwork during discovery. You see a working demo every two weeks regardless.
Appther is remote-first and does not keep a Manhattan office. Our US entity is registered in California, and the US-facing team keeps Eastern Time hours for New York clients, so stand-ups, demos and escalations fall inside your working day. A named senior engineer stays your single point of contact from kickoff through launch.
Yes. For NYDFS-regulated clients we build to Part 500 from the start: multi-factor authentication, role-based access, encryption of nonpublic information, audit logging, incident-response hooks and the third-party vendor documentation your CISO has to certify. For broker-dealers and advisers we design record-keeping and communications capture to satisfy SEC Rule 17a-4 and FINRA rules. Licensing and filings remain with you; the app is built so they are straightforward.
Yes. For most consumer, marketplace and internal apps we start from Flutter or React Native, because one codebase covers both stores on one budget. Where a product depends on hardware, heavy graphics, background processing or platform-specific features we recommend native Swift or Kotlin instead, and we make that call during discovery with the reasoning written down.
Compliance decisions are made in discovery, with your counsel at the table, before design begins. For the SHIELD Act that means a documented security program, encryption, access controls and a breach-response plan. HIPAA work means encryption, role-based access, audit logging and a business associate agreement when the data calls for one. For biometrics we follow the NYC biometric identifier law and, for apps that reach Illinois or Texas users, BIPA and CUBI as well: consent first, no sale, published retention. Each control is written up as we build it, so an examiner can trace it.
You own all of it. Code lives in repositories under your organization, store accounts are opened in your company's name, and infrastructure runs in a cloud account you control. We sign an NDA before discovery, assign intellectual property as each invoice is paid, and if you ever change vendors the handover is a matter of revoking our access.
The first month is hypercare: we monitor crashes, latency and store reviews every day and fix what surfaces. After that you choose a support tier with a written SLA, OS-update coverage, security patching and a monthly report on retention and performance. Regulated clients also get the evidence pack their annual NYDFS certification or HIPAA risk assessment needs.
Cost breakdowns, AI budgets and feature checklists we send New York clients before the first call, so the conversation starts from real numbers.
Tell us what the app has to do and who it is for. Straight answers on approach, scope, timeline and cost, from an engineer rather than a salesperson. Prefer email? Use our contact page.
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