We make apps for runners and tools for developers.
Young J Corp. is a software company in Hwaseong, South Korea. We make RunHUD, a large-type heart rate and pace display for treadmill runs; OnTrack, an audio interval timer for track workouts; and OGQuick, an API that turns a URL into a link preview image.
Two apps for runners, one tool for developers
Young J Corp. is a software company based in South Korea. We make mobile apps for runners and a web API for developers.
RunHUD reads heart rate, pace, and cadence directly from Bluetooth sensors and watches, and shows them in type large enough to read mid-run. OnTrack announces each step of an interval workout by audio, so you can keep your eyes on the track instead of your phone.
Running data in RunHUD and OnTrack is processed on your phone. Neither app connects to Garmin Connect or other fitness-platform accounts.
OGQuick is for developers and site owners who want link preview images generated automatically. You request an image with a single URL, and Korean and Japanese text renders with built-in fonts.
RunHUD
Real-time running data display for treadmill workouts. Connects to Bluetooth sensors (Garmin, Polar, Suunto, Stryd) and shows heart rate, pace, and cadence in large, glanceable format.
OnTrack
Interval training timer built for runners. Set target pace and distance, get audio alerts at every checkpoint, and train with precision using customizable workout structures.
OGQuick
An API that generates Open Graph (link preview) images from a single URL. Korean and Japanese fonts are built in, so text renders without broken characters.
Get in touch
Have questions about our products, partnership inquiries, or need developer support? We'd love to hear from you.
Gyeonggi-do, 18467, Republic of Korea