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Interactive water for Apple Watch

Slosh

Wear water on your wrist. Discover it on iPhone. Fifteen living water modes respond to motion, touch, and place.

Active development · watchOS + iOS · physical-device validation remains

Slosh calm ocean water experience

What it is

Slosh is a watchOS water instrument: look straight down into an ocean, tide pool, rain shower, or other authored water experience and let the wrist become the control surface.

Tilt the watch and the swell rolls with you. Shake it and the surface stirs. Tap it and a ripple spreads. SpriteKit fragment shaders provide the per-pixel water while SwiftUI carries the app shell.

Water, with provenance

The iPhone companion is the discovery and configuration surface. Reviewed places can carry live hydro conditions from NOAA and USGS while keeping the worn experience quiet, immediate, and free of telemetry.

All fifteen authored modes render in the simulator. Physical-watch tilt behavior, frame rate, battery impact, and App Store readiness remain open validation gates.

Built with

  • Swiftthe language the whole app is written in
  • SpriteKitshader that draws the moving water pixel by pixel
  • SwiftUIapp screens and mode picker on watch and phone
  • Core Motionreads wrist tilt and shake to move water
  • MapKitmap of reviewed water places on iPhone
  • WatchConnectivitysends the water you choose from phone to watch
  • NOAA and USGS public datareviewed-place readings in test builds, not a general live feed

Changelog

Milestones in plain English, newest first, to Nov 7, 2026

  • First build: fifteen distinct water modes for Apple Watch, each answering tilt, shake and tap.
  • In test builds, live NOAA readings for San Francisco Bay now shape how the water moves.
  • Added Monterey Bay and Lake Tahoe as reviewed places, each showing which readings it supports.
  • New iPhone companion browses places as a list or map and sends the chosen water to the watch.

Roadmap

What comes next. Plans, not promises, and no dates.

  • In progressTest on a real Apple Watch for tilt direction, frame rate, battery use and haptics.
  • PlannedBring the water itself to iPhone and iPad, including a bedside charging view.
  • In progressFind trustworthy real-water places beyond the three reviewed ones.
  • PlannedReplay past water conditions and show clearly labeled forecasts.