Apps, backends and smart contracts, built to last.

Since 2011 we have shipped Android apps with millions of installs, open-source libraries used by thousands of developers, and contracts that are live on Ethereum mainnet. We build it, ship it, and keep it running.

Start a project See our work
1M+installs of our most popular Android app
1000sof npm downloads a month for our open-source packages
2011first Android release, shipping ever since
3apps on Google Play, all still maintained

What we've built

Our own apps, apps we built for clients, and libraries. Ask us for the store and repository links.

Smart-home control app

Flutter · Android
Live

An independent app for a building-control system: lights, blinds, ventilation, heating, cameras and energy management, at home or remotely. Built on our own open-source client library.

Android system utility

Google Play · paid app
1M+ installs

Removes root from almost any Android device: cleans the system partition and restores the original files from backup. One purchase, all your devices.

Audio equalizer app

Google Play
100K+ installs

Five-band equalizer with bass boost, 3D surround, loudness and presets per genre.

Construction site management app

Enterprise · iOS and Android
Live

Mobile control centre for construction projects: site diary, photo documentation, defect reports, time and performance recording, and a shared project space for plans and documents. Built for a construction-software vendor; on Google Play and the App Store today.

Parking app

React Native · Android and iOS
Live

Real-time availability, navigation to the space, and payment, end to end. Built for a client, in production today.

Soulbound membership NFT

Solidity · Ethereum mainnet
Live

Non-transferable ERC-721 contracts that verify a magazine's subscribers on-chain and unlock access to its members' community. Built for a client; deployed and live on mainnet.

On-chain games and proofs of concept

Solidity · Ethereum
Archived

Game logic and token economics on-chain, plus smart-contract prototypes with web frontends, built to test ideas before committing to them.

Open-source projects

GitHub · npm
Maintained

Libraries and tools we publish and maintain in public. Our most-used package is downloaded thousands of times a month on npm.

What we do

Mobile apps, the backends behind them, smart contracts where they make sense, and the maintenance that keeps all of it running. One team for the whole thing.

Mobile apps

Flutter or React Native when one codebase makes sense, Kotlin or Swift when the app needs the platform.

  • Offline mode, push, payments, maps
  • App Store and Google Play releases
  • Hardware and IoT integrations

Backends

REST and GraphQL APIs on Node.js, C#, Java or Kotlin, PostgreSQL underneath, and monitoring so problems show up before users report them.

  • Authentication, payments, third-party APIs
  • AWS, Google Cloud, Firebase
  • Logging, metrics, alerts

Smart contracts

Solidity on Ethereum: contracts with full test coverage, the wallet and transaction flows in your app, and a plan for upgrades before anything goes on mainnet.

  • ERC-20, ERC-721 and custom contracts
  • Wallet connection and transaction handling
  • Testnet, audit preparation, mainnet deployment

Maintenance

We stay on after launch: OS updates, store policy changes, dependency upgrades, and the fixes that keep an app alive for years.

  • Crash reporting and monitoring
  • OS, SDK and store-policy updates
  • Documented handover whenever you want it

How a project runs

Four stages. Each one ends with something you can see and sign off, so the next stage never starts on assumptions.

Stage 1

Discovery

We work out what actually needs building and what it will cost. Usually that means cutting scope, not adding it. You leave with a list you agree with.

Scope · first draft Example12 → 7 items
  • Sign in with email and Google
  • Offline mode for site visits
  • Photo upload with annotations
  • Social login cut
  • Custom theming cut
  • Admin dashboard phase 2
✓ Agreed with youAgreed scope
Stage 2

Proposal

Architecture, milestones and a timeline you can hold us to, written down. You approve it before we write a line of code.

Proposal · milestones Examplev2 · final
  1. M1Auth, data model, first screensapproved
  2. M2Offline sync and photo uploadapproved
  3. M3Store submission and rolloutapproved
✓ Approved by youScope and price agreed in writing
Stage 3

Build and ship

You get installable builds to try on your own phone, not status reports. Problems surface while they are still cheap to fix.

New build Exampleready to install
Build 42 · internal testing

Offline sync, photo annotations, crash fix on Android 14.

Install on your device
✓ Tested by youAfter every milestone
Stage 4

Maintain or hand over

We stay on for fixes, OS updates and store policy changes, or hand over a documented codebase to your own team. Either way, it keeps running.

Releases Examplelive
  • v2.4.0OS update, dependency upgradescurrent
  • v2.3.1Store policy change
  • v2.3.0New feature, requested by users
  • v1.0.0Launchfirst release
✓ Still maintainedOr handed over, documented

Tell us what you're building

Email goes straight to the people who would build it. We'll tell you whether we're a fit and roughly what it would take, usually within a working day.

info@pinpong.eu No forms, no sales calls. Just email — or LinkedIn.