Tidewalk: Korea Tide Timer

Taking the kids to the sea? Know when to head back before the tide comes in.
Tidewalk was made to check the tides and know when to head back during a day at the sea with a child. On a mudflat or a sea road it is easy to lose track of time, so tap "Start crossing" or "I'm going in" and a countdown to the time you should be back on land appears in your notifications. Times are calculated from official KHOA tide predictions.

LIVE COUNTDOWN
- On a sea road, the deadline is when the road closes; at an official mudflat foraging spot, when foraging ends; anywhere else, when the water starts coming back in (low tide). Tidewalk sets your head-back time 30 minutes earlier
- The notification counts down every second and goes away an hour after the deadline
- Alerts 30, 15 and 5 minutes before, and at the head-back time (battery saving can delay them by up to an hour, so the countdown notification always shows the time left)
- End it with "I'm back" in the app
- If the water is already coming in, the app tells you not to go in

SEA ROAD OPEN TIMES — DAY AND NIGHT
- 13 Korean sea roads, including Silmido, Seonjaedo, Soyado, Udo and Seogeondo
- The official sea-parting index lists times between 09:00 and 18:00 only. Tidewalk calculates every open window of the day from predicted tide heights, including early morning and night (for sea roads with enough official samples)
- Nearest first, open ones on top, with time left: "Closes 16:34 · 3 h 34 min left"
- Detail: today's tide curve with the opening level and open windows, this week's open times, and the official index times side by side

TIDE TABLES
- Rising or falling now, and time to the next high or low tide
- Tide day (mulddae) and spring/neap strength, tide curve, high and low tide times and heights
- About 160 Korean stations, plus 90 Japanese ports such as Tsushima, Fukuoka and Osaka (JMA tide tables)

ACTIVITY INDEXES AND TIDE ALERTS
- Official KHOA marine indexes: sea fishing, mudflat foraging, sea parting, surfing and scuba
- Low-tide alerts, water-returning alerts and a weekend summary, quiet from 22:00 to 06:00 by default
- Alerts are scheduled on the device: no account needed

CALENDAR, WIDGET AND MARINE WEATHER
- A month of tides on one page: tide day, moon phase, holidays and low-tide times
- Home screen widget (small and medium) with the next high and low tide
- Sunrise, sunset, moonrise, moonset and twilight; hourly temperature, wind and wave height from KMA
- Tide heights adjusted to your location (KHOA TideBED, for reference)

No sign-up or login. Your location and countdowns stay on your device and are never stored or sent. Free, supported by ads.

Safety: the countdown is a reference time calculated from forecasts. Wind or low pressure can bring the water in earlier, so always follow official closures and local guidance first.

Data sources: KHOA tide predictions, marine indexes and TideBED; KMA short- and mid-range forecasts; KASI rise and set times (via data.go.kr). Japanese ports use JMA tide tables.

Tidewalk is made by PiFl Labs and does not represent KHOA, KMA, KASI, JMA or any other government agency.

Contact: support@pifl-labs.com

Recent changes:
What's new in 1.2.0 — Tide Friend is now Tidewalk
- Live countdown: tap "I'm going in" on Home or "Start crossing" on a sea road to see how long until you should head back, right in your notifications, with alerts 30, 15 and 5 minutes before
- Sea road open times for 13 Korean sea roads, with every window of the day (early morning and night included) where enough official samples exist
- Open the sea road list straight from Home