Grayson Ho
Verified Expert in Engineering
iOS Developer
Grayson is a senior iOS engineer experienced in building mobile products with millions of daily active users and consumer products that scale fast. He has worked as a senior mobile developer at well-known companies, contributing to a finance super app at Revolut, a crypto wallet and exchange for Blockchain.com, and a top downloaded note-taking app at GoodNotes. Grayson understands the whole product development process, handling features from design to public launch.
Portfolio
Experience
Availability
Preferred Environment
MacOS, Xcode, Swift 5, iOS, TypeScript, JavaScript, Front-end
The most amazing...
...products I've built are a finance app for Revolut and an educational note-taking app for GoodNotes, constantly ranked as number one in the App Store.
Work Experience
Senior iOS Engineer
Revolut
- Led an 8-person team to develop a joint account feature for the Revolut Retail app, enabling users to spend on a shared digital wallet.
- Fixed miscellaneous bugs and made minor improvements to the payment transactions feature, resulting in a 99% crash‑free rate for 19 million weekly active users.
- Built the Safari extension for the Revolut card wallet.
Senior DApp Engineer
Wombat Exchange
- Built decentralized applications (DApps) using TypeScript with React and Solidity for smart contracts.
- Created an analytics dashboard using GraphQL and React to show transaction volumes and summaries.
- Handled a protocol with over $20 million of total value locked and a record of $60 million in daily volume transactions.
iOS Engineer
Blockchain
- Led and shipped the new single sign-on feature for the iOS mobile application using SwiftUI, Combine, and the Composable Architecture pattern. It resulted in 41% more sign‑ups and 37% fewer customer support requests.
- Modularized various crypto transaction features with a Clean Architecture pattern that reduces the CI build time by 24%.
- Implemented a design system to improve the developer experience, achieving an internal NPS of 4.2 out of 5.
iOS Engineer
GoodNotes
- Led and shipped a notes-sharing platform on iOS to 10 million monthly active users of GoodNotes 5. Worked with RxSwift, CQRS pattern, and conflict‑free replicated data types.
- Set up CI/CD pipelines for app deployments using Fastlane and Circle CI.
- Introduced a release cadence framework that boosted team‑wise productivity.
Data Engineer
Tovala
- Developed data pipelines to lay out foundations for data intelligence to drive business decisions. Python and SQL.
- Developed dashboards and scripts to show insights about company performance.
- Developed data science models for meal sales predictions using Ridge Regression Model.
Software Engineer
Movella
- Developed internal management software using Node.js and SQL for managing hardware device inventory.
- Developed a motion tracking algorithm using MATLAB to visualize the motion trajectory of the latest sensor technologies.
- Improved the company process by setting up system design review processes.
Technical Evangelist
Microsoft
- Developed chatbot applications for retailers to resolve customer queries using Microsoft Intelligence Services.
- Developed multiple proofs of concepts using the latest Microsoft technologies.
- Spoke at multiple conferences across universities and technical communities.
Experience
Quintics
https://testflight.apple.com/join/61g11YYaI am the founder and developer of the application.
Wombat Exchange
https://app.wombat.exchange/I've contributed to the project as a DApp engineer, frequently interacting with smart contract developers.
Cryptocurrency Price Tracker
https://github.com/graysonhyc/BraveWalletHackConflict-free Replicated Data Type in Python
https://github.com/graysonhyc/lww_elements_set_pySkills
Languages
Swift 5, TypeScript, Swift, Swift 2, Swift 3, CSS, HTML, Dart, Kotlin, Objective-C, JavaScript, Solidity, Python 3, Go, SQL
Frameworks
SwiftUI, iOS SDK, Flutter, UIKit, React Native, Combine, Angular, Next.js, Core Data, Cocoa Touch, Redux, Unity, iOS SceneKit, AWS HA, ARKit
Libraries/APIs
React, RxSwift, Node.js, WebRTC, Core Animation, REST APIs, Codable, Core Image, Camera API
Tools
Xcode, GitHub, MetaMask, Atlassian, Jira, Figma, CircleCI, TestFlight, CallKit, Moya, VPN, Prisma
Paradigms
Model View ViewModel (MVVM), Agile Project Management, Mobile Development, Requirements Analysis, Test-driven Development (TDD), Automated Testing, Microservices, Agile, DevOps
Platforms
MacOS, iOS, Mobile, Blockchain, Android, Firebase, Google Cloud Platform (GCP), Docker, Amazon Web Services (AWS), Azure, Desktop, Safari
Industry Expertise
Project Management
Other
Mobile Apps, Native Mobile Apps, Product Management, Front-end, Project Planning, Product Strategy, APIs, Architecture, Decentralized Applications, Decentralized Systems, Web3, Amazon RDS, Full-stack, Animation, A/B Testing, CI/CD Pipelines, Team Leadership, Video Chat, Wireless Protocols, Software Architecture, eCommerce, Technical Leadership, Startups, Scalability, Planning, Finance, App Store, Subscriptions, User Interface (UI), User Experience (UX), UI Animation, WebSockets, Video Streaming, Web Development, iPad, Image Manipulation, Video Editing, AVFoundation, Virtual Reality (VR), Non-fungible Tokens (NFT), iOS Camera, Safari Extensions, Minimum Viable Product (MVP), Data Structures, Wireless, Widgets, 3D Modeling, Augmented Reality (AR), Objective-C++, Instant Messaging, PSD to Swift
Storage
MongoDB, Cloud Firestore
Education
Bachelor's Degree in Computer Science
University of Hong Kong - Pokfulam, Hong Kong
Student Exchange Program in Computer Science
Yale University - New Haven, CT, USA
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