Sisnex

Services

What we do

We take mobile products from first specification to the store listing, and keep them running afterwards. You can engage us for a complete product or for one part of it.

How engagements are billed

Model Suited for Billing
Fixed-scope project A defined app or feature set Milestone invoices against an agreed quote
Time and materials Evolving scope, ongoing product work Monthly invoice for hours worked, at an agreed hourly rate
Maintenance plan Apps already in production Fixed monthly fee, billed in advance

All prices are quoted in US dollars before work begins. Invoices can be paid by card or bank transfer; card payments are processed by Stripe. See our refund and cancellation policy for details.

01

iOS development

Native iPhone and iPad apps in Swift and SwiftUI, built to Apple's Human Interface Guidelines and ready for App Store review.

  • Swift, SwiftUI and UIKit
  • Widgets, notifications, in-app purchases with StoreKit
  • Integration with HealthKit, MapKit, Apple Pay, Sign in with Apple
  • TestFlight distribution and App Store submission

02

Android development

Native Android apps in Kotlin and Jetpack Compose, tested across the device sizes and OS versions your users actually have.

  • Kotlin, Jetpack Compose, Android Jetpack libraries
  • Google Play Billing, Firebase Cloud Messaging, Google Maps
  • Background work and offline-first data sync
  • Play Console setup, internal testing tracks and release management

03

Cross-platform apps

One codebase for iOS and Android with Flutter, when time to market and budget matter more than platform-specific detail.

We will tell you honestly whether cross-platform fits your product. For most business apps it does; for apps that depend heavily on platform features, native is usually the better long-term choice.

  • Flutter with platform channels for native features
  • Shared business logic, platform-appropriate UI
  • Single release pipeline for both stores

04

Backend and APIs

The APIs, databases and admin tools behind the app — designed for mobile clients, with authentication, push notifications and payments.

  • REST and real-time APIs, primarily in Go
  • PostgreSQL, authentication, role-based access
  • Push notification delivery, file storage, background jobs
  • Payment integration with Stripe, App Store and Google Play server notifications
  • Deployment, monitoring and backups

05

Product and interface design

Product definition, user flows and interface design, delivered as clickable prototypes you can test before development starts.

  • Requirements workshops and written specifications
  • User flows, wireframes and high-fidelity screens
  • Clickable prototypes for early user feedback
  • App Store and Google Play listing assets

06

Maintenance and support

Monthly plans that keep a production app current — OS updates, dependency upgrades, crash monitoring and small improvements.

Apple and Google release major OS versions every year and regularly raise store requirements. An app that is not maintained eventually stops being accepted for updates.

  • Compatibility releases for new iOS and Android versions
  • Crash and performance monitoring with agreed response times
  • Security patches and dependency upgrades
  • A monthly allowance of hours for improvements