Highlights

What I'm working on and what I'm most proud of

Pins for Pinboard (Free with IAP, iOS, macOS, Swift): A modern Pinboard app. Currently in active development. Follow its development on Twitter.

Pocket Quotes (Free, iOS, Swift): Collect your favorite quotes from famous people, books, TV shows, etc. Currently in active development.
NetNewsWire (Open-source contribution, macOS/iOS, Swift): Cross-platform RSS feed reader. I helped adding NewsBlur support to the app.

Writing Kit (Commercial, iOS, Objective-C): Powerful text editor with advanced researching tools for bloggers and writers. Achieved 20,000+ paid downloads. Featured by Fast Company, Ars Technica, Macworld, etc. Also featured in books like Hand Held Hollywood’s Filmmaking with the iPad & iPhone and The Writer’s iPad.
Cyberspace (Commercial, iOS, Objective-C): Productivity-focused web browser for iOS. Achieved 5,000+ paid downloads. Featured by Macworld, GigaOm, etc.

Exercise Genius (Open-source, iOS, Objective-C): Exercise tracking app for runners. Winner of Best Student Team and Microsoft’s Best Use of HealthVault APIs prizes at Cajun Code Fest hackathon (Louisiana, USA).

TumblrStats.com (Open-source, Web, Ruby, Sinatra): Learn random facts about your tumblelog: when you registered your Tumblr account, how many posts you made, how often you create a new entry, etc. Achieved 500,000+ visits.

aTutor for iPhone (Open-source, iOS, Objective-C): Mobile client for aTutor, an open source eLearning CMS by OCAD U (Toronto, Canada). Sponsored by Google as part of the Google Summer of Code program.

My Setup (Free, Web): Collection of interviews with people from different industries about what they use to get their job done. Inspired by Uses This.
ngaunhien.me (Free, Web, PHP): Read funny comic strips on each page load. In Vietnamese, the name translates to “random”. Achieved 300,000+ visits.

Custom Smilies (Open-source, Plugin, WordPress, PHP): Add emoticons to blog entries and comments. Achieved 10,000+ downloads and made Mashable’s 30+ plugins for WordPress comments and 300+ tools for running your WordPress blog lists.

Reg Assistant (Free, Windows, AutoIt): Import and export Windows registry in one click. Achieved 10,000+ downloads.
Folder Tweaker (Free, Windows, AutoIt): Customize background image and icon for folders in Windows Explorer. Achieved 20,000+ downloads.

Have a look at my open- and closed-source projects as well.