Matthew Knippen, Developer in Chicago, IL, United States
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Matthew Knippen

Verified Expert  in Engineering

Swift Developer

Chicago, IL, United States
Toptal Member Since
October 30, 2013

Matthew has been building iPhone and iPad applications since the release of the iPhone SDK in 2008, working on over 60 applications in his career. He holds a bachelor's degree in computer science from the Illinois Institute of Technology. His best strengths are Native iOS development and product development and management.


Charge Running
MapKit, Agile Software Development, Git, GitHub, Cocoa Touch, Xcode, iOS...
Zwiffer, Inc.
Agile Software Development, Git, GitHub, Cocoa Touch, Xcode, iOS, JavaScript...
Git, GitHub, Cocoa Touch, Xcode, iOS, Machine Learning, Python, Swift, iOS SDK...




Preferred Environment

Git, GitHub, Xcode, TextMate, OS X, Zsh, Swift, JSON

The most amazing...

...application I've built is Charge Running, an application that provides real-time running classes with a live coach through your mobile phone.

Work Experience


2016 - PRESENT
Charge Running
  • Developed an application for iPhone and Apple Watch with thousands of paying users.
  • Sent over 30 versions of the application to the App Store, with each one showing improvement to our sales funnel and user experience.
  • Built and led a team of trainers, marketing, PR, and business people.
  • Worked with an overseas team to launch a native Android application.
  • Went through YCombinator, the world's best startup incubator. Raised three rounds of funding.
Technologies: MapKit, Agile Software Development, Git, GitHub, Cocoa Touch, Xcode, iOS, Analytics, Swift, iOS SDK, iOS Native Libraries, JSON, Geospatial Data, iPad, Firebase, API Integration, Development, App UX

President, Lead iOS Developer

2009 - PRESENT
Zwiffer, Inc.
  • Developed 60+ iOS apps from startups to the Fortune 500.
  • Provided work to clients such as AT&T, General Assembly, Bloc, bottega8, DIRECTV, and Smyte.
  • Mentored junior developers in iOS, Swift, Xcode, and analytics.
  • Used advanced CoreImage features including face detection to detect when a user is blinking in a photo for the application NoBlink.
  • Built an app in almost every category on the App Store, from Games and Sports & Entertainment to Business & Productivity.
Technologies: Agile Software Development, Git, GitHub, Cocoa Touch, Xcode, iOS, JavaScript, CSS3, HTML5, PHP, Objective-C, Swift, iOS SDK, iOS Native Libraries, JSON, iPad, Firebase, API Integration, Development, App UX

Lead iOS/Machine Learning Developer

2017 - 2019
  • Built an SDK for other developers to display an offerwall used by thousands.
  • Provided insight in key architectural decisions for iOS, Android, and Unity SDKs.
  • Utilized machine learning and AI to build a fraud protection system for our ad network.
  • Built an advanced caching system for images and videos that runs seamlessly in the background.
  • Implemented semantic versioning throughout the three SDKs.
Technologies: Git, GitHub, Cocoa Touch, Xcode, iOS, Machine Learning, Python, Swift, iOS SDK, iOS Native Libraries, API Integration, Development

Founder, CEO

2014 - 2015
Alligator Games
  • Led game design and development for three titles.
  • Hired artists, animators, designers, and developers for products I designed.
  • Learned marketing, branding, PR and other important skills that an entrepreneur needs to know.
  • Used Swift exclusively, becoming an expert in Apple's new programming language.
Technologies: GameKit, Agile Software Development, Git, GitHub, Cocoa Touch, Xcode, iOS, Game Design, Swift, iOS SDK, iOS Native Libraries, JSON, iPad, Firebase, API Integration, Development

Senior iOS Developer, Product Manager

2012 - 2013
Deck5 Software, Inc.
  • Developed iOS applications for various Fortune 500 corporations and personal R&D projects.
  • Built a team of excellent people to work with, including developers, designers, project managers, and interns.
  • Used new business and marketing techniques to make iOS applications successful in the App Store.
  • Developed product management skills and learned what it takes to make a tech product successful.
  • Created the Forte by Korn/Ferry Product, allowing users to become better employees in many Fortune 500 organizations.
  • Built the Application DECKFOLIO, the go-to app for learning stocks and options on the iPad.
Technologies: Agile Software Development, Git, GitHub, Cocoa Touch, Xcode, iOS, JavaScript, Ruby on Rails (RoR), Objective-C, iOS SDK, iOS Native Libraries, JSON, iPad, API Integration, Development

Senior iOS Developer

2012 - 2012
Designory, Inc.
  • Built an application for Infiniti cars that is used in retail stores today.
Technologies: Git, Cocoa Touch, Xcode, iOS, SQL, Objective-C, iOS SDK, iOS Native Libraries, iPad, Development

Systems Engineer

2010 - 2012
Lextech Global Services
  • Developed nearly 20 different applications for various high-profile companies.
  • Built a custom drag-and-drop inventory search product for Sonic Automotive. This application had to search 25,000 cars instantly using Core Data.
  • Used UIGestureRecognizers to build a 3D viewing model by splitting the object into pictures. This allowed the original iPad to render in full quality without losing performance.
  • Used Infinite Peripherals Hardware to build two different applications involving barcode signing and credit card transactions. Lightning Sale won an award at iOSDevCamp in 2010.
  • Worked in small teams to accomplish large goals.
  • Learned how to structure time to meet tight deadlines for clients.
Technologies: Agile Software Development, Cocoa Touch, Xcode, iOS, JavaScript, Java, C, Objective-C, iOS SDK, iOS Native Libraries, JSON, iPad, API Integration, Development

Mac Specialist

2008 - 2010
Apple, Inc.
  • Learned how to position the perfect selling points of a Mac Computer, iPod and iPhone and the ideal way to position someone in buying a computer with accessories.
  • Had several weeks with the most sales in the store.
  • Became very good at suggesting additional products based on the customer’s needs.
  • Learned strong customer interaction and how to address the needs of the customer.
  • Asked to help lead training for every new Apple employee in the entire region.
Technologies: MacOS

My Interactive Application Portfolio

TapFame holds all of the applications I have built that are currently on the App Store, allowing you to see screenshots, technologies used, reviews, and more.

Charge Running

Featured in "New Apps We Love"
#1 Recommended Fitness Training App!

Over 35,000 runners can't be wrong! Charge Running is the most motivating, encouraging, and social way to run!

Charge hosts LIVE running classes from the comfort of your own neighborhood or treadmill. Each live run brings runners from all over the world together in one class where you can run, chat, and compete on our Live Leaderboard for the #1 spot!

Picture this: You wake up in the morning, open up Charge, and see 10+ LIVE runs happening that day. You decide to join the 8 AM run, grab your shoes and headphones, and suddenly you're running LIVE with a dozen other REAL people. You compete against them for distance as if they're running right beside you. Sounds pretty awesome, right?

That's not even the best part.

Each class is hosted and DJ'd by a LIVE, certified running coach, who will motivate, encourage, and empower you to run your best! You have the choice of joining classes varying in difficulty from light walk-to-runs for beginning runners, to hard tempos for those who are training for their next race. Just throw on your shoes, pop in a pair of headphones, and our amazing coaches will take care of the rest!

AdGem - Mobile Ad SDK
A mobile SDK that allows you to view several different types of ads in your application, and earn extra revenue for your game or app!

NoBlink - Always Take the Perfect Photo!

NoBlink allows you to always take the perfect photo without a single person blinking in it! Ranked in the Top 10 Photo & Video applications in 4 countries.

DECKFOLIO - Options Education Made Simple

Investing can be a challenging endeavor even for professionals. So retail investors need every advantage they can get. Deckfolio was created for both experienced and aspiring investors to help increase their investing skills and returns through the use of options. Many investors fail to recognize the power that options can provide for both portfolio risk reduction and leverage; so they're missing out. But their reticence is frequently due to their misperception of options, along with innate options complexity. Deckfolio leverages the communications and social graph capabilities of Twitter with innovative graphical analysis features into a simple and engaging options education experience. Download it and give it a try!

Korn/Ferry Forte

Forte is an innovative application from Korn/Ferry International that provides an engaging personal development platform for employees.

Sonic Automotive - Auto Search

Auto Search from Sonic Automotive guides you through an easy yet comprehensive search process to connect you to the vehicle and dealer that is the best fit for your needs. Best of all, you can access the Sonic inventory website’s most popular features on-the-go!

The Pampered Chef

Pampered Chef® Consultants, this is your official app!

Stay on top of your business anytime, anywhere. Quickly manage your contacts and calendar, set up Shows, enter orders, and submit Shows. It all syncs automatically to your data on Consultant's Corner*, so you're always up to date! Plus, you can view current and upcoming Host & Guest Specials and browse all of our products. You truly can do business wherever you are!

Diode - Award Winning Game

Diode is an addictive, race-against the clock arcade game that matches precision with crazy-fast speed. Diode was voted Best Game at iOSDevCamp in 2010. See a video of Diode in action:
2008 - 2012

Bachelor's Degree in Computer Science

Illinois Institute of Technology - Chicago, IL, United States


Deep Learning Specialization



Firebase iOS SDK, iOS Native Libraries, Flurry, Facebook iOS SDK, iRate, Core Image, Facebook API, PlayHaven, Core Animation, Core Graphics, SpriteKit, X (formerly Twitter) API


Apple Keynote, Git, Xcode, Crashlytics, RevMob, VirtualBox, GitHub, GitHub Pages, Adobe Photoshop, Coda 2, Charles, Subversion (SVN), Zsh, Adobe Illustrator


iOS SDK, UIKit, Core Data, Cocoa Touch, ImageIO, EventKit, Core Foundation, AFNetworking, MapKit, Core Location, CFNetwork, StoreKit, Core Motion, GameKit, Ruby on Rails (RoR), AudioToolbox, Core Bluetooth


Swift, Objective-C, HTML5, Python, GraphQL, SQL, CSS3, Ruby, Java, C, Haskell, JavaScript, PHP


Model View Controller (MVC), Object-oriented Programming (OOP), Agile Software Development, Concurrent Programming, Class-based OOP, Refactoring, Mobile Development, Rapid Prototyping, UX Design, Unit Testing, Scrum, REST, Key-Value Observing (KVO), Pair Programming, Extreme Programming, Continuous Integration (CI), Test-driven Development (TDD)


Firebase, MacOS, Parse, Keychain, iOS, iCloud, Heroku, Amazon Web Services (AWS), OS X, Arduino


JSON, SQLite, MongoDB, Amazon S3 (AWS S3), NoSQL, PostgreSQL, MySQL


Product Design, AVFoundation, Accounts, Multithreading, Lean Development, Game Design, Sales, Product Management, Product Development, App Store, iPad, API Integration, Development, Analytics, Security, Computer Graphics, Geospatial Data, App UX, Machine Learning, Computer Science, User Interface (UI)

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