Chen

ChenApple-platform engineerSeattle

I build small, careful apps for Apple platforms and keep notes along the way.

I work in SwiftUI, watchOS, HealthKit, CloudKit, and on-device AI. I care about useful software, privacy, and getting the details right.

See the apps Read the notes
On the benchOct 2026
Latest note
A new home for Stash
Oct 8
On the desk
AirPods Max 2 — Midnight
Oct 13
Apps
15 apps, extensions and plugins
All
Writing
61 notes since 2015
Archive
01

Apps

Native, private-by-default apps. Built one at a time, looked after for the long run.

All 15 apps →
JSON viewer & Safari

Structly

Browse JSON as a tree, sortable table or formatted source, search keys and values, and format JSON pages in Safari on iPhone, iPad and Mac.

iPhone · iPad · MacExplore
Health & fitness

LiftCoach

Plan strength routines, log every set, and see how your training adds up. Live workout stats, muscle maps, exercise demos, and AI coaching help you train with purpose.

iPhone · iPad · Apple WatchExplore
02

Writing

Notes on Swift, Apple platforms, and what I learn while building, in English and the original Chinese.

Archive →
  1. A new home for Stash 1 min

    The new Stash website is live, with a preview of an app for keeping copied things and lifting the useful pieces.

  2. Keeps 1.4.3 submitted for review: smoother currency scrolling 2 min

    Keeps 1.4.3 (112) has been submitted for App Review with smoother currency scrolling and fixes for item details and punch calendar layout.

  3. Keeps 1.4.0: every use counts 3 min

    Keeps 1.4.0 brings paper price tags, punch-card goals, photo stages, better search, and automatic backups to iPhone, iPad, and Mac.

  4. Let your things log themselves in Keeps 3 min

    Three Shortcuts automations that record a use in Keeps without opening the app: an app that opens, an NFC tag on a water bottle, and a car that connects over Bluetooth.

  5. LiftCoach on iPhone Duo 4 min

    A first look at LiftCoach on iPhone Duo: two pages when it opens, a seated mode that turns the folded top half into a screen for the bench, controls in the side bar, and a Live Activity that fits the new island.

  6. LiftCoach is on the App Store 2 min

    LiftCoach 1.0.0 is available for iPhone, iPad, and Apple Watch. Plan strength routines, log every set, and see how your training adds up.

03

Gear

Things I use, with photos and notes on why they stay.

All gear →