Sailing boats at anchor at sunset — HoldFast anchor alarm app
Anchor Alarm App
iOS

HOLDFASTAnchor Drag Alarm for iPhone

Your anchor.
Watched.

HoldFast anchor watch app running on an iPhone

★★★★★  Rated 5.0 · Free on the App Store

Download on the App Store
See the app →
HoldFast anchor drag alarm
HoldFast anchor watch app

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The Reality

Why You Need HoldFast Anchor Alarm

Most anchor alarm apps rely on your phone's GPS — but they don't tell you when they've lost it. Your phone falls asleep, GPS quietly drops, and you're anchored with no protection and no warning. HoldFast is built differently. Accurate GPS is our obsession. If your phone loses lock, HoldFast fires the alarm — not silence. It stays awake through the night, through the squall, through the tide turn. Set your radius, share your watch code with crew ashore, and review your full GPS track come morning. The moment your boat moves beyond your set radius, the alarm fires. Sound, vibration, notification — through the lock screen, at full volume. Because an anchor alarm that sleeps is no alarm at all.

Sailing yacht anchored in a turquoise bay
GPS Position 39°24.3′ N · 002°56.7′ E ANCHOR WATCH ACTIVE
Sailor relaxing at anchor with HoldFast anchor alarm app running on iPhone
Relax at anchor
Monitoring boat anchor position remotely from ashore using HoldFast watch code
Monitor from ashore
Sleeping safely at anchor with GPS drag alarm protection from HoldFast app
Sleep easy
Rated 5.0 on the App Store
From 6 ratings · iPhone

“A great app that is intuitive to use and will allow a good nights sleep whilst the boat is at anchor. Recommended!”

Fathom II · App Store review

“Brilliant app. Using this, in combination with my other instruments, just gives me a bit of extra confidence remaining at anchor! Wish I'd had this sooner!”

RowingDonkey · App Store review

Why Sailors Trust HoldFast

30,000+ NM
Built by a liveaboard sailor with 8 years at anchor
Never Silent
Fires the alarm if it loses GPS — instead of failing quietly
Lifetime Option
$9.99 once for life — or $4.99/year, no lock-in
No Signal Needed
The drag alarm runs on GPS alone, in any anchorage

Rates

Two ways to premium:
$4.99 a year, or $9.99 once for life.

Free
Always Free
No card required
$0
  • Anchor Setting
  • Set anchor at current location
  • Choose a point on the map
  • Alarm
  • Full drag alarm — sound & vibration
  • Push notifications through lock screen
  • Radius
  • Circular radius — 5 to 200 m
  • Monitoring
  • Continuous foreground GPS monitoring
Download Free
Annual
Per Year
Billed yearly · cancel anytime
$4.99
  • Everything in Lifetime
  • All premium features below
  • Anchor Setting
  • Compass-bearing relative placement
  • Alarm
  • Full drag alarm · choose your alarm sound
  • Radius
  • Circular radius 5–200 m + custom boundary
  • Monitoring
  • True background GPS (screen off)
  • Battery saving mode
  • GPS track history
  • Remote watch — share a live code
Go Yearly
Best Value
Lifetime
Forever
One payment · no renewals · beats Annual after 2 years
$9.99
  • Anchor Setting
  • All free placement modes
  • Relative position via compass bearing — aim your phone to set distance and direction
  • Alarm
  • Full drag alarm — sound & vibration
  • Choose your alarm sound
  • Radius
  • Circular radius — 5 to 200 m
  • Custom boundary — sketch around hazards like reefs, shoals or sandbars
  • Monitoring
  • True background GPS — monitors while screen is off
  • Battery saving mode
  • GPS track history — view your overnight movement on the map
  • Remote watch — share a code so crew ashore can monitor live
Go Lifetime

Start free — no account or card required. Upgrade any time: $4.99 a year, or $9.99 once for Lifetime (no renewals).

Available on the App Store · iOS only · Prices in USD

For Crew & Family

Watch From Anywhere

Generate a code in the app. Anyone can open a browser, enter four digits, and see your anchor position in real time — no app required on their end.

Updates live — no manual refresh needed
Code expires when you end the watch
Multiple watchers simultaneously
Open Watch Page
Enter a watch code
4
2
7
1

Enter the 4-digit code from the HoldFast app to start watching the anchor in real time.

FAQ

Common questions
HoldFast uses your iPhone's GPS to record your anchor position the moment you start the watch. It continuously compares your boat's live position to that point. If your boat drifts beyond your chosen radius — anywhere from 5 to 200 metres — the alarm fires instantly with sound, vibration and a push notification, even with the screen locked.
Yes — HoldFast is free to download and use. The free tier gives you a full drag alarm, circular radius control and GPS monitoring. Premium features — background GPS, track history, remote watch sharing, custom radius drawing, compass-based anchor placement, battery saving mode and custom alarm sounds — are available for $4.99 a year, or a one-time $9.99 Lifetime purchase with no renewals.
Yes — with a Lifetime account. Set your anchor alarm before you leave the boat, then go ashore. Generate a 4-digit watch code in the app. Anyone with an internet connection — crew, marina staff or family — can open a browser, enter the code, and see your boat's position updating live. No app required on their device.
Set your radius to cover your scope plus a small safety margin — typically chain length plus boat length. The slider adjusts from 5 to 200 metres and the live map updates in real time so you can see exactly what area you are watching. Lifetime users can also draw a custom boundary to stay clear of specific hazards like reefs or sandbars.
Background GPS is a Lifetime feature. With Lifetime access, HoldFast continues monitoring even when your screen is off or you are using another app. The alarm fires through the lock screen at full volume. Free users should keep the app open and the screen active during the watch.
The anchor watch and drag alarm work fully without mobile signal — they rely on GPS, not a data connection. The remote watch share feature does require internet on both devices, as it relays position data via a secure server.
Yes — with Lifetime access. HoldFast records your full GPS track throughout the anchor watch session. Use the history scrubber to replay exactly where your boat moved, when it moved, and whether it stayed within your radius. Free users do not have track recording.

New to anchoring, or want to get the most from your alarm? Explore our anchoring guides — from setting an anchor alarm to getting your scope right.