01Untwine
Make room for the hard part.
A task manager that treats emotional difficulty as something the interface can acknowledge.
- The feeling belongs to the task.
- Offer a smaller next move.
- Two endings. Equal care.
- One character, two platforms.
Timothy Yang / Design engineer
One moment, designed all the way down.
Four apps I designed and built myself. Each case study follows the one interaction the rest of the app hangs on, from the first idea to the spring that settles it.
02Everywhen
Getting people to come back.
Turning a place-based learning app into a daily where-and-when game, from the shape of a day to the physics of one sheet.
- Ask one question at a time.
- An era first. Then a year.
- Let the answer become a story.
- Keep the places you discover.
03Sleep Map
A habit with something to keep.
A gentle bedtime ritual that makes accumulated progress visible on a map.
- Make tonight easy to find.
- A missed night is not an eraser.
04Ice Age Life
A complex world, within reach.
A prehistoric life simulation shaped around readable choices and a cohesive illustrated world. Reached 146 first-time App Store downloads and recorded three in-app purchases over a 90-day reporting period (July 10–October 7, 2026).
- Reveal the system through choices.
- Many icons. One visual world.
More case studies
