Christopher Arriola, Developer in Berkeley, United States
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Christopher Arriola

Verified Expert  in Engineering

Android Developer

Berkeley, United States
Toptal Member Since
May 4, 2016

Christopher is a mobile engineer with over seven years of experience creating native Android and iOS applications. He has a strong product sense and an eye for design. His portfolio includes a social network with millions of users, to real-time messaging and more. He also is a strong advocate of RxJava and is currently writing a book called "Reactive Programming on Android with RxJava" (



Preferred Environment

Vim Text Editor, Xcode, Android Studio, OS X

The most amazing...

...thing I've built is several Android apps from the ground up.

Work Experience

Founder and Developer

2016 - PRESENT
Mynah Software LLC
  • Began building the Android app from the ground up for a client.
  • Utilized ReactiveX principles using RxJava.
  • Developed a data layer that abstracts local database read/writes and network operations.
  • Implemented a continuous integration system that runs unit tests after every commit and subsequently distributes a new APK to internal users if all tests pass.
  • Developed a material design compliant application.
Technologies: Android, Java

Mobile Full-stack Engineer

2015 - 2016
  • Worked as part of a team to launch Operator's first iOS application, which was featured on the front page of the App Store during Black Friday.
  • Built a Python OData implementation.
  • Implemented a throttle mechanism for handling large concurrent requests.
  • Migrated data from an older database to a redesigned/refactored database.
  • Built the first Operator landing page.
Technologies: iOS, Android, JavaScript, Objective-C, Python, Java

Co-founder and Android Developer

2014 - 2015
Green Halo Labs
  • Developed the Android app from the ground up for various Silicon Valley startups including Sprig, Fluc, and Sincerely.
  • Open sourced a library on Android for autocompletion of an email address when logging in. The library was featured in an AndroidWeekly newsletter.
  • Blogged and wrote about various Android tips/tricks on the Green Halo Labs blog.
  • Trained junior-level developers from various startups to enable them to be autonomous and take over the codebase.
  • Implemented a reusable module/library that was used by 4 applications for a client.
Technologies: Java, Android

Mobile Engineer

2012 - 2014
  • Contributed to launch Edmodo's first iPad application. Implemented the authentication flow and various core components on the iPad app.
  • Created the post stream, authentication screen, and various framework components for Edmodo's Android app.
  • Created a tablet optimized Android application.
  • Trained and mentored interns to contribute to features on the iPad application that were eventually shipped to production.
  • Reimplemented the Android application to be a comply to modern design standards.
Technologies: Objective-C, Java, iOS, Android

Software Designer II

2011 - 2012
  • Built a web server using Jetty.
  • Developed a computer vision application for HP R&D using webOS and OpenCV.
  • Create a hand detection algorithm using a Kinect, IR, and RGC camera using OpenCV.
  • Designed an API in Jetty that allows a client application to interface with the computer vision system.
  • Implemented a 3-camera calibration mechanism using fiducials on a template image.
Technologies: OpenCV, C++, Java, JavaScript


An Android open source library I built for auto-completing email in an EditText view.


An Android Wear application that reminds you to be present.

A GitHub gist for a custom Android ImageView for a top cropped image.
2009 - 2010

Master of Science Degree in Computer Science

University of Pennsylvania - Philadelphia, Pennsylvania, USA

2005 - 2009

Bachelor of Science Degree in Biomedical Engineering

Rutgers University - New Brunswick, New Jersey, USA


RxJava, SQLAlchemy, OpenCV


GitHub, Git, Android Studio, Vim Text Editor, Xcode


Unit Testing, Continuous Integration (CI), Functional Programming, Functional Testing




Java, Swift 2, Python, C++, CSS, HTML, Swift, JavaScript, Objective-C


Android, iOS, OS X, Heroku


MySQL, PostgreSQL, Redis, Amazon S3 (AWS S3)


Computer Vision, Software Design

Collaboration That Works

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