Publication
Write Once, Deploy Everywhere: When to Go Native?
https://www.toptal.com/developers/app/native-vs-hybrid-apps-pros-and-cons
Joel is currently unavailable
Joel Frank
Verified Expert in Engineering
Mobile Application Developer
São Tomé de Covelas, Portugal
Toptal member since December 26, 2019
Bio
With a PhD in computer science and over 18 years of experience creating mobile applications, Joel has a passion for creating flawless user interfaces and applications that exceed expectations. In addition, his knowledge of databases and back-end requirements gives him a deep understanding of an application's complete architecture.
Portfolio
Kilsar, Inc.
Swift, iOS, ARKit, Augmented Reality (AR), Mobile Apps, SwiftUI, Node.js...
Caterpillar
Front-end, Full-stack, iOS, Heroku, Amazon Web Services (AWS), Android, Kotlin...
Bleu Tech Enterprises, Inc.
Bluetooth, Bluetooth Low Energy (LE), iOS, Android...
Experience
- iOS - 17 years
- Android - 12 years
- Amazon Web Services (AWS) - 8 years
- Swift - 7 years
- Flutter - 6 years
- SOLID Principles - 6 years
- Node.js - 3 years
- Augmented Reality (AR) - 2 years
Work Experience
Lead Flutter Developer | AR Engineer
2022 - PRESENT
Kilsar, Inc.
- Architected and implemented a Flutter-based augmented reality (AR) training application that allowed for solo AR sessions and a shared AR experience by embedding the AR session into a multi-person video teleconferencing (VTC) call.
- Led the joint front- and back-end team effort to define the system architecture's microservices for a modular, reusable, performant, and cost-efficient back end.
- Translated the company's strategic roadmap from long-term deliverables to day-to-day operations for the mobile team while reliably meeting deadline after deadline.
- Maintained the team's focus on quality by continually adapting, improving, and polishing the designs under changing requirements.
Technologies: Swift, iOS, ARKit, Augmented Reality (AR), Mobile Apps, SwiftUI, Node.js, Serverless, AWS Lambda, Front-end Development, Mobile Development, Mobile UI, Mobile UX, Video Streaming, Networking, VoIP, Auth, Audio Streaming, Location Services, Mobile Architecture, GPS, Internet of Things (IoT), Amazon Web Services (AWS), Streaming, Apps, iTunes Connect, TypeScript, Back-end, Full-stack, Software Design, Mobile Applications, Flutter, Dart, SOLID Principles, DevOps, Serverless Framework, Amazon Cognito, Identity & Access Management (IAM), Keychain, Application Security, Security, SSL, SSL Certificates, Artificial Intelligence (AI), Data Modeling, Cross-platform App Development, Firebase Realtime Database, Apple Push Notifications, Silent Push Notifications, Data Synchronization, ChatGPT, OpenAI, APIs, Payment Gateways, Online Payments, Consumer-facing Products, Camera API, Social Networks, Videos, Snapchat, Banuba, Large Language Models (LLMs), Riverpod, BloC, Image Processing, Audio Processing, Amazon EC2, Amazon S3 (AWS S3), Stripe, Software Architecture, Front-end, In-app Purchases, AI Integration, Natural Language Processing (NLP), OpenAI API, Text-to-Speech (TTS), Speech-to-Text (STT), Full-stack Development, Django, App UI, Google Analytics
Lead Flutter Mobile Engineer
2018 - 2022
Caterpillar
- Managed the small but highly effective engineering team that revolutionized how a Fortune 50 company creates and maintains software.
- Created the core Flutter application that became The Cat App—Caterpillar's central flagship mobile application (Apps.apple.com/us/app/cat-app-fleet-management/id1258931644).
- Developed and evaluated a single application side-by-side against three frameworks: Kotlin Multiplatform Mobile (KMM) with Native SwiftUI, React Native, and Flutter.
- Mentored several team members, from being on the verge of termination to being senior, reliable engineers who now help to drive the team's vision and mentor others.
- Transformed the team's strategic roadmap into actionable sprint plans while meeting the ever-changing requirements of the company's product owners and stakeholders.
Technologies: Front-end, Full-stack, iOS, Heroku, Amazon Web Services (AWS), Android, Kotlin, Kotlin Multiplatform Mobile (KMM), Architecture, Firebase, Swift, Java, Mobile, Fastlane, Core Data, Core Animation, REST APIs, UX Design, Team Leadership, UIKit, Model View ViewModel (MVVM), Unit Testing, UI Testing, Apple Design, JavaScript, TypeScript, ARKit, Bluetooth, Bluetooth Low Energy (LE), Mobile App Development, Redux, Azure Cloud Services, API Integration, SwiftUI, Azure DevOps, Dashboards, Figma, User Experience (UX), UI Animation, User Interface (UI), Test-driven Development (TDD), Git, Core Location, XML Interface Builder (XIB), AVFoundation, Combine, Mobile Apps, Scrum, GitHub, JSON, XML, Technical Leadership, CI/CD Pipelines, Jira, Augmented Reality (AR), iOS Native Libraries, Design Patterns, Mapbox, Node.js, Azure, Technical Architecture, Leadership, Front-end Development, Mobile Development, Mobile UI, Mobile UX, RxSwift, Video Streaming, Networking, Google Cloud Platform (GCP), iPad, Amazon Transcribe, Auth, Python, Location Services, Mobile Architecture, GPS, Apps, iTunes Connect, Back-end, Software Design, Mobile Applications, Flutter, Dart, SOLID Principles, DevOps, Serverless Framework, Amazon Cognito, Identity & Access Management (IAM), HIPAA Compliance, Keychain, Application Security, Security, SSL, SSL Certificates, Cross-platform App Development, Apple Push Notifications, Silent Push Notifications, Data Synchronization, APIs, Payment Gateways, Plaid, Plaid API, Online Payments, Consumer-facing Products, Camera API, Videos, Snapchat, Banuba, Large Language Models (LLMs), Riverpod, BloC, Image Processing, Audio Processing, Amazon EC2, Amazon S3 (AWS S3), Stripe, Software Architecture, In-app Purchases, AI Integration, Text-to-Speech (TTS), Full-stack Development, Django, App UI, Google Analytics, FlutterFlow
Lead Mobile BLE Engineer
2020 - 2021
Bleu Tech Enterprises, Inc.
- Designed and implemented core BLE libraries for merchant and client, iOS, Android, and UWP, to facilitate encrypted payment transactions via Bluetooth.
- Optimized the BLE bandwidth while allowing messages of arbitrary size in multiple communication channels.
- Coordinated with a diverse team spanning three continents to meet all project milestones ahead of schedule.
Technologies: Bluetooth, Bluetooth Low Energy (LE), iOS, Android, Universal Windows Platform (UWP), Elliptic Curve Cryptography, Swift, Java, C#, SDKs, Mobile, Fastlane, REST APIs, Team Leadership, Unit Testing, WebSockets, Mobile App Development, API Integration, SwiftUI, User Experience (UX), Test-driven Development (TDD), Git, XML Interface Builder (XIB), Mobile Apps, Payment Gateways, Payment APIs, Scrum, GitHub, JSON, XML, Technical Leadership, CI/CD Pipelines, Jira, iOS Native Libraries, Design Patterns, Cryptocurrency Wallets, Mobile Wallet, Fintech, Node.js, Technical Architecture, Leadership, Front-end Development, Mobile Development, Mobile UI, Mobile UX, eCommerce, RxSwift, Networking, Google Cloud Platform (GCP), iPad, Auth, Python, Location Services, Mobile Architecture, GPS, Internet of Things (IoT), Amazon Web Services (AWS), Apps, iTunes Connect, Software Design, Mobile Applications, SOLID Principles, DevOps, Serverless Framework, Amazon Cognito, Identity & Access Management (IAM), PCI Compliance, Keychain, Application Security, Security, Cross-platform App Development, Apple Push Notifications, Silent Push Notifications, APIs, Online Payments, Consumer-facing Products, Amazon EC2, Stripe, Software Architecture, Front-end, Back-end, In-app Purchases, Full-stack Development, App UI, Google Analytics
CTO | Lead Engineer
2020 - 2021
Dr Lullaby
- Assisted in writing research grant proposals for the NSF, documenting the application's innovative approaches toward sleep therapy.
- Revamped the existing system architecture to improve performance, maintainability, and scalability.
- Contributed to guide the long-term vision of the project.
Technologies: Front-end, iOS, Android, Back-end, Full-stack, Reinforcement Learning, Swift, Swing, Java, Objective-C, Architecture, Mobile, Fastlane, Core Animation, REST APIs, UX Design, Team Leadership, CTO, UIKit, Model View ViewModel (MVVM), Unit Testing, UI Testing, WebSockets, Apple Design, Mobile App Development, API Integration, User Experience (UX), UI Animation, User Interface (UI), Test-driven Development (TDD), Git, Core Location, XML Interface Builder (XIB), Mobile Apps, Payment APIs, Scrum, GitHub, JSON, XML, Technical Leadership, CI/CD Pipelines, iOS Native Libraries, Design Patterns, Mobile Banking, Technical Architecture, Leadership, Front-end Development, Mobile Development, Mobile UI, Mobile UX, Networking, iPad, Auth, Location Services, Mobile Architecture, Apps, iTunes Connect, Mobile Applications, Flutter, SOLID Principles, HIPAA Compliance, Keychain, Application Security, Security, APIs, Payment Gateways, Online Payments, Consumer-facing Products, Amazon EC2, Stripe, Software Architecture, In-app Purchases, App UI, Google Analytics
Co-founder | Lead Engineer
2013 - 2016
GroupTing
- Co-led a small team to design and implement a web-based, group coordination application that utilizes a PostgreSQL database supporting a Grails-based server with an AngularJS-based client.
- Managed a remote quality assurance team to provide detailed testing results in time with a rapid development and deployment schedule.
- Worked in coordination with the marketing team to provide agile-based user feedback—a development cycle that resulted in an efficient and responsive product development strategy that was in line with users’ needs.
Technologies: Agile, Firebase, PostgreSQL, MongoDB, Mobile, CocoaPods, Facebook API, CSS, MySQL, iOS Native Libraries, Design Patterns, Mobile Development, Mobile UI, Mobile UX, eCommerce, Networking, Google Cloud Platform (GCP), Auth, Location Services, Mobile Architecture, Amazon Web Services (AWS), Apps, iTunes Connect, Software Design, Mobile Applications, SOLID Principles, Keychain, Application Security, Security, Software Architecture, Front-end, In-app Purchases
Senior Software Engineer
2015 - 2015
Ipsy
- Designed and developed Ipsy’s iOS mobile application that services thousands of users and receives an overall five-star rating (a link to the app can be found in my Experience section).
- Created a novel interface allowing the mobile and web applications to seamlessly communicate.
- Assisted with mentoring junior engineers by teaching them proper engineering techniques and assimilating them into Ipsy's culture.
Technologies: Swift, Agile, Firebase, Xcode, iOS SDK, Objective-C, iOS, Java, Android, Mobile, CocoaPods, Facebook API, CSS, MySQL, Payment Gateways, Payment APIs, iOS Native Libraries, Design Patterns, Fintech, Mobile Development, Mobile UX, Android API, Auth, Location Services, Mobile Architecture, Apps, iTunes Connect, Full-stack, Software Design, Mobile Applications, PCI Compliance, Security, Software Architecture, Front-end
Development Engineer
2006 - 2011
Applied Signal Technology
- Designed, implemented, and maintained a Qt-based graphics library that allowed the user to view and manipulate numerous STM-256 signals down to the sub-VGC level in real-time.
- Developed and maintained a multithreaded C++ client/server application for signal analysis to continually meet the customer’s evolving requirements. Communication between the client and the server was done via CORBA.
- Manipulated SDH and PDH signal structures to perform various operations on the information in the data streams.
- Conducted design and code reviews for all team members in an effort to both improve the product as well as guide junior members of the team.
Technologies: Agile, C++, Networking, Mobile UX, Android API, Telecommunications, VoIP, Mobile Architecture, iTunes Connect, Software Architecture, Front-end
Project History
Cat® App: Fleet Management
Efficient equipment management starts with the Cat® app. Track the location and health of your equipment, order service and parts, and increase utilization in just a few taps. Staying on top of your fleet has never been easier.
I was responsible for leading the team as well as personally responsible for 100% of the iOS codebase.
I was responsible for leading the team as well as personally responsible for 100% of the iOS codebase.
Ipsy's iOS Mobile Application
https://apps.apple.com/us/app/ipsy-beauty-makeup-tips/id1016673544I designed and developed Ipsy’s iOS mobile application that services thousands of users and received an overall 5-star rating.
Draw Together
A real-time collaborative drawing application that allowed multiple artists to work together, share ideas, and create artwork. The key technical challenge the application overcomes is the dynamic drawing stack becoming too large as more and more edits and changes are done to the drawing, which would otherwise make the application slow down and become non-performant.
Risk Runner
A multiplayer and AI-based Risk application (en.wikipedia.org/wiki/Risk_(game)) that integrated the user's movement and steps to determine their attack power during the game. The application supported both HealthKit as well as Fitbit.
Education
2011 - 2017
PhD in Computer Science
University of California, Santa Cruz - Santa Cruz, CA, USA
2006 - 2008
Master of Science (MSc) Degree in Computer Science
San Jose State University - San Jose, CA, USA
2001 - 2006
Bachelor of Science (BSc) Degree with Honors in Computer Science
San Jose State University - San Jose, CA, USA
Skills
Libraries/APIs
HealthKit, Core Image, AVKit, Firebase iOS SDK, Firebase Android SDK, SpriteKit, Core Animation, REST APIs, iOS Native Libraries, Auth, Camera API, ReactiveX, CocoaPods, Facebook API, Fitbit API, Node.js, RxSwift, Android API, Plaid API, Stripe, OpenAI API, Core Graphics, WebRTC
Tools
Apple HealthKit, Xcode, Interface Builder, Auto Layout, Firebase Analytics, Git, XML Interface Builder (XIB), iTunes Connect, Apple Push Notifications, Google Analytics, Fastlane, Android Studio, Sirikit, Firebase Cloud Messaging (FCM), Figma, GitHub, Jira, Plaid, Snapchat, Amazon Transcribe, Amazon Cognito, ChatGPT
Languages
Swift, JavaScript, XML, Dart, Java, C++, Python, Objective-C, HTML, CSS, Kotlin, TypeScript, GraphQL, C#
Frameworks
iOS SDK, UIKit, Core Bluetooth, iOS SceneKit, GameKit, Flutter, SwiftUI, Core Location, Android SDK, ARKit, Core Data, Redux, Combine, Serverless Framework, Riverpod, Django, Swing
Paradigms
Model View ViewModel (MVVM), MVC Design, Model View Controller (MVC), Model View Intent (MVI), Model View Presenter (MVP), Requirements Analysis, Agile, UX Design, Unit Testing, Test-driven Development (TDD), Scrum, Design Patterns, Mobile Development, Dependency Injection, Concurrent Programming, Azure DevOps, HIPAA Compliance, REST, DevOps
Platforms
Bitrise, Mobile, iOS, Android, Firebase, Amazon Web Services (AWS), iAd, Bluetooth Low Energy (LE), Mapbox, Google Cloud Platform (GCP), Keychain, Banuba, Amazon EC2, FlutterFlow, Unix, Heroku, AWS Lambda, Universal Windows Platform (UWP), Azure, Twilio
Storage
Cloud Firestore, Firebase Realtime Database, MySQL, JSON, PostgreSQL, MongoDB, Data Synchronization, Amazon S3 (AWS S3), Realm, Azure Cloud Services
Industry Expertise
Telecommunications
Other
APIs, Models, Model View, SDKs, Carthage, Code Architecture, Agile Sprints, Architecture, Technical Leadership, Leadership, Front-end, Bluetooth, Team Leadership, UI Testing, Apple Design, Mobile App Development, API Integration, User Experience (UX), UI Animation, User Interface (UI), Mobile Apps, Payment Gateways, SOLID Principles, Front-end Development, Mobile UI, Mobile UX, iPad, Location Services, Mobile Architecture, Apps, Software Design, Mobile Applications, Cross-platform App Development, Silent Push Notifications, Consumer-facing Products, BloC, Software Architecture, Full-stack Development, App UI, Mobile Streaming, Firebase Cloud Functions, AVFoundation, Networking, Back-end, Full-stack, CTO, WebSockets, Payment APIs, CI/CD Pipelines, Augmented Reality (AR), Lambda Functions, Serverless, Fintech, Mobile Banking, Technical Architecture, eCommerce, Video Streaming, VoIP, GPS, Internet of Things (IoT), Streaming, Identity & Access Management (IAM), Application Security, Security, Online Payments, Social Networks, Videos, Large Language Models (LLMs), Image Processing, In-app Purchases, AI Integration, Text-to-Speech (TTS), OAuth, Kotlin Multiplatform, Reinforcement Learning, Elliptic Curve Cryptography, Kotlin Multiplatform Mobile (KMM), Animation, Algorithms, Google Fit, SVG Animation, Dashboards, Cryptocurrency Wallets, Mobile Wallet, Audio Streaming, PCI Compliance, SSL, SSL Certificates, Artificial Intelligence (AI), Data Modeling, OpenAI, Audio Processing, Natural Language Processing (NLP), Speech-to-Text (STT)
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