Qtum Wallet

Cryptocurrency Mobile Wallet for Android and iOS

  • Blockchain
  • Mobile
  • Cryptocurrency
  • UI/UX
  • Smart Contracts
  • DApps

Mobile multi-currency wallet for Android and iOS. Supports ERC20 tokens and smart contracts. Secure management of funds and seamless linking to DApps.

Feb 2018 – Oct 2018

Work done

  • iOS crypto wallet
  • Android crypto wallet
  • Qtum blockchain API integration
  • Smart contract builder launch
  • Cryptocurrency wallet design & feature prototyping


Back in 2016, our team worked side by side with the Qtum team to help the company launch its own scalable open-source Qtum blockchain platform. PixelPlex helped the team to develop a Decentralized Governance Protocol (DGP), allowing for blockchain parameter customization, and engaged in the implementation of a block explorer, a PoS consensus on the Bitcoin fork, along with integration with Ethereum and WASM virtual machines. The results of this collaboration effort are described in detail here.

Qtum Foundation Ltd., a Singapore-based corporation specializing in mobile decentralized apps (DApps), launched its platform in September 2017. With a market cap of $4B, Qtum is one of the 40 most popular digital currencies as of January 2020.

To date, there are nearly 6,000 Qtum nodes operational around the world, most of which are located in the US and run on AWS and Google Cloud. With over 200 launched DApps, the Qtum project is backed by some of the most notable blockchain players and executives from well-known global tech companies.


Having recently introduced upgrades with EVM and launched the first x86 VM smart contract on the mainnet, Qtum Foundation turned to PixelPlex for custom mobile crypto wallet development. They needed a convenient cryptocurrency wallet interface with additional features for offline stacking, communication with the blockchain, and diving into every perk of the Qtum platform.

Our team was responsible for:

  • Building iOS and Android multi-currency crypto wallet specifically for the Qtum blockchain;
  • Achieving a smooth and fast connection to the Qtum network;
  • Securing the app and user transactions from hacker attacks, malware, phishing, and unauthorized remote access.


The result we delivered was the Qtum mobile cryptocurrency wallet, an easy-to-use yet powerful tool for tamper-proof direct transactions, powered by end-to-end encryption mechanism. We introduced the support of ERC20 tokens and management of several accounts to facilitate sending, receiving, and storing of all the user’s coins in one app.

The cryptocurrency wallet encodes private keys and all transaction data right on the mobile device. We implemented a client-side encryption feature to make the user account and all transactions private before this information touches a third-party server.

In-App Smart Contract Builder

PixelPlex team also delivered a user-friendly smart contract builder to help easily draft smart contracts with the help of ready-made templates right from your mobile device, using just the Qtum wallet. The tool enables the users to even create their own templates, which is very helpful when you need to use smart contracts for different purposes on a daily basis.

In the end, we produced two separate implementations of the Qtum cryptocurrency wallet for iOS and Android.


Multiple cryptocurrency support

All Ethereum-based ERC20 tokens are supported in the app, enabling users to create multi-asset accounts.

Direct access to Qtum

Through the connection to the Qtum blockchain, the users manage tokens and assets, import/export accounts, and connect to DApps.

Real-time transaction history

Convenient finance flow tracking with an activity log of transactions and smart contract usage.

Exceptional security

Local private key and data storage with many layers of security: PIN, 2FA, and Android / iOS crypto wallet auto-lock.

Smart Contract Builder 

Simple template-based interface for fast creation, customization, and launch of smart contracts.

Use of smartphone biometrics

User authentication and crypto wallet unlock through Touch ID / Face ID or Android’s Fingerprint.

Multiple platform compatibility

Flexible cryptocurrency wallet backup and restore feature on iWatch, iMessage, and Android Wear.

Transaction templates

Transaction and smart contract templates for often used addresses can be created to save time.

QR code as a payment request

QR code generation that leads directly to a payment request widget.

Interactive pop-ups

Helpful app navigation tips, funds in USD equivalent. Conversion rates to track cryptocurrency price.

Beautiful UI themes

Quick swipes, day and night mode, user-friendly interface, and intuitive experience.

Qtum news feed

Access to all the latest updates, improvements, tips from the Qtum team, and news from the world’s top crypto sources.


Swift, Kotlin, Node.js, WebSocket, MongoDB, Keychain, DeepLink


  • 2 Mobile Developers
  • 2 Full-Stack Developers
  • QA Engineer
  • UI/UX Designer
  • Project Manager


8 months

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