How can we help?
Email us and a person will reply, usually within two business days.
hello@ebbandflood.appCommon questions
Where do the currents and tides come from?
From NOAA's official predictions for each current and tide station. Where NOAA publishes a full prediction, the app shows it unchanged. Where NOAA publishes only the day's max flood, max ebb and slack times, the app estimates the speeds in between.
How accurate are the estimates?
In Washington waters, 133 of 191 current stations show NOAA's own prediction, unchanged. At the other 58, the speeds between NOAA's slack and max times are estimated, and when we tested this method against NOAA's full predictions, 97.3% of estimates were within 0.3 knots. The accuracy page shows how we tested it and where estimates are least certain. The same numbers are in the app under ⚙︎ › How accurate is Ebb & Flood?
Can I use Ebb & Flood to navigate?
No. Ebb & Flood is for planning, not navigation. Currents and tides are predictions, not observations: they don't include wind, river runoff or air pressure, which can change real conditions a lot. Carry a chart and compass, check conditions on the water and use your own judgment.
Does it work without cell signal?
Yes. Currents and tides are always on your phone. The map (about 137 MB for Washington waters) saves itself the first time you're on Wi-Fi, or tap Save now in the Map menu. Check it says "Saved on this phone" before you go. Satellite and the NOAA chart need a signal.
Which areas are covered?
Washington waters: the San Juans, Puget Sound, the Strait, the coast and the Columbia, including Oregon and Canadian stations on shared water. More states: coming later, each tested separately before it's added.
Can I share a trip?
Yes. Open a trip and tap Itinerary for a day-by-day plan: launch, rest stops, camp, layover and take-out, with times, distances, the current on each leg and the tide at each stop. Tap a stop's name to rename it, then tap Share itinerary to send it as a PDF or a text message, with a map link to every stop.
Where do the launch and camp sites come from?
From Washington State Parks, the Washington Department of Fish and Wildlife, the Washington Department of Natural Resources, the Washington Department of Ecology, the Washington Water Trails Association and OpenStreetMap. Each card shows only what its source publishes, and links to the site's own page for reservations, fees and closures. See Data sources & credits.
A launch, beach or campsite is missing. How do I tell you?
Open the menu (⚙︎) and tap Suggest a missing site, or tap the suggestion link when a search finds nothing. Move the map so the ＋ is on the spot and tap Send. Your email app opens with the location filled in; add what's there and send. We check every suggestion against public sources before it goes on the map.
A site is in the wrong place or has closed. How do I tell you?
Tap the site, then Report a problem at the bottom of its card. Your email app opens with the site's details filled in; add what's wrong and send. Or email us at hello@ebbandflood.app.
How do I cancel my subscription?
On iPhone, open Settings, tap your name, then Subscriptions, and choose Ebb & Flood. On Android, open Google Play, tap your profile icon, then Payments & subscriptions. Canceling during the free trial means you won't be charged.
Do my trips sync between my devices?
On iPhone and iPad, trips sync through your own iCloud, so they appear on your other devices signed in to the same Apple ID. You can turn this off in the menu (⚙︎). On Android, trips are backed up to your Google account with your phone's regular backup, so they come back when you reinstall Ebb & Flood or set up a new phone. Android doesn't sync trips live between two devices yet.
What happens to my trips if Pro ends?
They stay saved on your phone. You can still open any trip and view or share its itinerary; planning new trips and editing existing ones need Pro. Renew any time and everything is editable again.
I got a new phone. How do I get my subscription back?
Sign in with the same Apple ID or Google account, open Ebb & Flood and tap ⚙︎ › Restore purchases (it's also on the Pro screen).