Rucking Tracker: Loadline
Pack weight, honest calories
Free · In‑App Purchases · Designed for iPhone. Not verified for macOS.
Pack weight is the point of a ruck. Loadline tracks it as a first-class number and computes calories from the load you carried, not from a walk.
Loadline is a rucking tracker built around one number: what is on your back.
Every other fitness app treats a loaded march as a walk. Loadline uses the Pandolf load-carriage equation, the standard for military load research, so calories reflect your body weight, your pack weight, your speed, the grade and the ground. A 35 lb ruck up a gravel hill is not a stroll, and your numbers should say so.
• The load gauge. Your current pack as a share of body weight, always on screen, with the 10–20 % band most people train in marked on the rail.
• The load ladder. Where you are and what the next step up weighs, so progression is a decision rather than a guess.
• Presets and gear. Build packs from plates, rucksacks and water; pick one and Start.
• Live tracking from iPhone or Apple Watch, with auto-pause that waits for you to actually stop, mile or kilometre splits, a Live Activity on the Lock Screen and the Dynamic Island, and spoken splits if you want them.
• A route you can move. Every ruck ends with an interactive Apple Maps route, an elevation strip and a summary built for a glance.
• Apple Health. Each ruck is saved as a Hiking workout with Loadline's calories and your pack weight in the workout's metadata, so Health and your rings see the load.
• Import a GPX file or an existing Health workout and log the weight after the fact.
• Weekly recap, standards to project your pace against, a share card with an optional privacy zone, CSV export.
Local-first. No account, no analytics, no tracking. Your routes never leave your phone unless you share them.
Calories are estimates. Loadline is not medical advice. Start near 10 % of body weight and add load slowly.
Loadline Pro is an auto-renewable subscription billed through your Apple Account; the yearly plan starts with a 7-day free trial. Manage or cancel it in Settings.
Terms of Use: https://synap1e.com/terms
Privacy Policy: https://synap1e.com/loadline/privacy
Ratings & Reviews
The developer, synap1e, 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 Linked to You
The following data may be collected and linked to your identity:
- Health & Fitness
- Location
- Contact Info
- User Content
- Identifiers
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Synap1e LLC
- Size
- 16.5 MB
- Category
- Health & Fitness
- Compatibility
Requires iOS 18.0 or later.
- iPhone
Requires iOS 18.0 or later. - Mac
Requires macOS 15.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 2.0 or later. - Apple Watch
Requires watchOS 11.0 or later.
- iPhone
- Location
- This app may use your location even when it isn’t open, which can decrease device battery life.
- Languages
- English
- Age Rating
13+
- 13+
- Contains
Messaging and Chat
User-Generated Content
Health or Wellness Topics
Social Media
- In-App Purchases
Yes
- Loadline Pro Monthly $4.99
- Loadline Pro Yearly $29.99
- Copyright
- © 2026 Synap1e LLC