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Stephen Z. Mobile App Developer

Stephen Z.

  • Columbus, OH
  • Over 20 years
  • Part-time (less than 40 hrs a week)
Stephen is now available for hire Hire Stephen

I have been developing native Android and iOS apps since 2012. Prior to focusing on mobile app development, I built websites and web applications for all sizes of companies (starting around the dot-com era).

Previously, I worked for early stage startups (Zero Longevity, Bump) as a lead developer and manager, as well as several digital agencies (Resource/IBM iX, Dynamit/Willowtree, Mills James) where I built websites and mobile apps for companies of all sizes. I also spent a year from 2018-2019 as a freelancer before I was hired on by one of my clients full-time.

Most recently, I created Castle, a podcast player for iOS and Android that generates transcripts which you can mark, save, and share with others.

I love building things for other people and am excited to build something for you!

For more work samples, please see:

Skills and experiences

Skills and experiences

Zero Longevity Science

Lead Android Engineer November 2018 - March 2022

Big Sky Health started as a client of mine as I developed the initial Zero Fasting Android app. After the
first version of the app was built, I came on full time to lead and contribute to Android development
• Developed Zero Android, a popular intermittent fasting app, from the ground up
• Managed, grew, and lead the Android team day-to-day
• Established and evolved a scalable and performant app architecture for Zero
• Estimated and designed technical solutions for new features
• Wrote and tested code for new features and review pull requests
Technologies: Android Studio, CircleCI, Coroutines, Dagger, Jetpack Compose, Kotlin, Room


Mobile Development Lead October 2014 - March 2018

As a mobile engineering lead at Willowtree, I focused on creating Android apps for our clients and
managing the mobile development team.
• Managed a team of native mobile developers
• Developed Donatos Pizza Android App
• Developed and provided support for a configurable, white-labeled Android e-commerce plugin for
Alliance Data to use with their clients
• Developed the Hilton Grand Vacations on-resort experience Android app
• Wrote project estimates and technical documentation
Technologies: Dagger, Java, Kotlin, node.js, RxAndroid, SQL


Senior Developer December 2012 - Oct 2014

I was responsible for architecting and developing mobile apps, websites and web applications at IBM iX.
• Co-architected and developed the ColorSnap native Android app for Sherwin-Williams
• Created an API (for Sherwin-Williams) used to “paint” a color over a surface on an image
• Developed an iOS image filter prototype for Bath & Body Works
• Co-developed a hybrid (Cordova) mobile app for Wendy’s mobile ordering
• Built a prototype VSX fitness hybrid app
• Part of a team developing the front-end of
• Built the front-end for a Kohl’s Pinterest contest website
• Contributed code to company sponsored open source projects
• Developed a custom Pinterest API for integration with Kohl’s content
Technologies: Backbone.js, CSS3, Grunt, HTML, Java, JavaScript, jQuery, Objective-C, PHP, Sass

Mills James

Mills James logo Senior Web Applications Developer September 2010 - December 2012

At Mills James, I developed client-driven Android and iOS apps, semantic and responsive websites, and
web applications.
• Architected and developed the UI of an iPad app for Cintas sales representatives
• Designed and developed native Android photo storyboarding app
• Developed hybrid Android and iOS country club app. Architected and built a REST service layer.
• Developed a PHP content management system for VitalSigns digital signage
• Designed and developed (front and back-end) responsive websites for multiple clients.
• Wrote proposals and estimates, created tech documentation, and presented to clients
Technologies: Backbone.js, C#, CSS3, HTML, Java, JavaScript, jQuery, MySQL, PHP, SASS, Wordpress, Yii Framework

Educations and Certifications

Bachelor of Science - Computer Science and Engineering

The Ohio State University 2000-2004
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