Redesigned for iOS 26: anti-icing holdover & allowance times from FAA and Transport Canada guidance, with live METAR autofill and a Lock Screen timer.
Holdover Calculator is a pre-departure decision tool for pilots facing winter operations. It returns the applicable anti-icing holdover or allowance time from FAA or Transport Canada published guidance, based on the actual weather, the de/anti-icing fluid applied, and your aircraft configuration.
DESIGNED FOR iOS 26
Built for iOS 26 and its Liquid Glass interface. The pilot answers a sequence of focused questions; the app shows the matching table cell, the published range, and a continuously interpolated estimate within that range.
KEY FEATURES
• Holdover and allowance times from the current FAA Holdover Time Guidelines and Transport Canada HOT Guidelines.
• Live weather autofill via the NOAA Aviation Weather Center — closest METAR or any ICAO you search.
• Manual entry always available when stations are out of range or you want to model conditions ahead.
• All four fluid types (Type I through Type IV) with both generic-table and specific-brand selections.
• Active Frost allowance and Ice Pellet allowance with a 90-minute takeoff-window tracker.
• Chart Notes surfaced inline, with active conditions (cold-soaked wing, OAT thresholds, etc.) flagged so you see only the notes that matter right now.
• App Estimated time — a continuous interpolation across OAT and precipitation intensity, shown alongside the FAA Recommended low end of every published range.
• Countdown timer with Live Activity on the Lock Screen. Minutes and seconds below an hour; hours and minutes above. The wall-clock "Ends at" reference is always shown to the second.
• Apple Watch companion for the crew member running the timer.
• Cockpit Sync — share one running timer across the flight deck. Link two to four pilots' devices over a direct, local Wi-Fi and Bluetooth connection; the captain approves every change, and the link re-establishes itself automatically if a device locks or briefly drops out of range. No account, no internet, no server.
• Readable on the ramp. Tap any advisory note — or any setting's description — to enlarge it in a comfortable card sized for reading-distance glasses.
• In-app notices. Occasional important notices (app updates, time-critical information) appear in the app, with a Messages inbox to revisit them. Opt out anytime in Settings; critical safety notices always show.
• FAA or Transport Canada as the global default, with per-calculation overrides.
• Local or Zulu time display; 12- or 24-hour clock.
PRE-DEPARTURE DECISION ONLY
This app is an advisor. The pilot in command remains solely responsible for verifying that the selected time is appropriate for the actual conditions, fluid, and aircraft at the moment of departure. Always cross-reference the current published holdover tables.
DATA SOURCES
• FAA Holdover Time Guidelines (current revision)
• Transport Canada Holdover Time Guidelines (current revision)
• NOAA Aviation Weather Center (aviationweather.gov) for live METAR observations
SUBSCRIPTION
Holdover Calculator is an auto-renewable annual subscription, with a free trial for new subscribers. Pricing is shown in the app before you subscribe.
• Payment is charged to your Apple ID at confirmation of purchase.
• The subscription renews automatically unless cancelled at least 24 hours before the end of the current period.
• Your account is charged for renewal within 24 hours before the period ends.
• Manage or cancel anytime in your Apple ID account settings.
• Any unused portion of a free trial is forfeited when you purchase a subscription.
PRIVACY
Location is requested only to identify the nearest weather station; your coordinates are sent solely to NOAA to run that query and are never stored or shared with us. No ads, no analytics, no tracking.
Privacy Policy: https://kilolimallc.github.io/legal/holdover-calculator/privacy.html
Terms of Use (EULA): https://kilolimallc.github.io/legal/holdover-calculator/terms.html
Disclaimer: https://kilolimallc.github.io/legal/holdover-calculator/disclaimer.html
You should say someplace WHAT the price of the annual subscription is!It may be a great app, but I’ve spent too much money on useless aviation apps to risk spending money on this. A one week trial, and or put the cost up front, would make me a lot more willing to try.
Pilot
Flypicker
App is simple to use, very straightforward. I tested its accuracy against the 2014 published numbers. They seemed jive almost perfectly. The only issue to mention is I can't renew this year. I can't get past the 1st instruction "click to renew." Otherwise great app.
Works ok
Jerseyreddevil
My main complaint is that the only option is to have an automatic renewal. I have been inconvenienced several times trying to get refunds for things I no longer want. Apple should require the option of turning down automatic renewals!!!
Professional pilot
f1fanman
Awesome application, makes computing holdover times a breeze.
Version 2.1.1
• In-app notices. Holdover Calculator can now show the occasional important notice — app updates and time-critical information — right in the app, as a card you can dismiss. They're pulled from a public file: no account, no tracking. Revisit past notices anytime from the new Messages item in the ••• menu, and turn them off in Settings. Critical safety notices always show.
Plus reliability and clarity improvements throughout. Fly safe.
PRIOR
Version 2.1
• Organization deployment for flight departments. Holdover Calculator can now be licensed across a managed fleet through Apple Business Manager and MDM — no per-device Apple Account or App Store sign-in required. Contact us to set it up.
• Read it at a glance. Tap any orange advisory note — or any setting's description — to enlarge it in a comfortable card sized for reading-distance glasses. Drag down or tap Done to dismiss.
• Cockpit Sync now correctly identifies Mac devices in the nearby-pilots list (they previously appeared as "iPad").
• Settings and Help no longer close on an accidental swipe — tap Done to dismiss, so a long scroll isn't lost.
• Includes the 2.0.1 fix for restoring an active subscription on a new device.
Version v2.1.1
The developer, Kilo Lima Management, LLC, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Privacy practices may vary, for example, based on the features you use or your age. Learn More
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
