Markline: Benchmark Hunting
Find and log NGS survey marks
About
Discover and log over 793,000 U.S. survey marks offline. This app provides detailed information on benchmark locations, allowing users to record findings with photos and notes. Navigate to marks using your preferred map application.
What's New in Markline
1.1.10
September 27, 2026
bug fixes
Subscriptions & In-App Purchases
$3.99
Markline Unlock
Permanent field guide access. No subscription.
Developer apps
FAQ
Does Markline have ads?
No, Markline is ad-free. The app focuses on providing a seamless user experience for benchmark hunting without interruptions from advertisements.
How much does Markline cost?
Markline is free to download and offers three days of full access. After the trial, an optional one-time unlock is available for continued access. There are no subscriptions or automatic charges.
What devices does Markline support?
Markline is available on Mac, iPhone, and iPad, providing a versatile experience for users across Apple devices.
Is Markline suitable for children?
Markline has an age rating of 4+, making it suitable for younger users. The app's content is generally appropriate for a wide audience interested in outdoor exploration and data collection.
How often is Markline updated?
The latest version of Markline is 1.1.10, and it was last updated on September 27, 2026. This indicates a commitment to ongoing development and maintenance.
Can I use Markline without an internet connection?
Yes, Markline is designed for offline use. The app bundles over 793,000 U.S. survey marks, allowing you to find and log them even without a signal.
What kind of data can I log with Markline?
You can log your recoveries, noting whether a mark was found, not found, or destroyed. You can also add a photo and a note to each recovery log.
Where does Markline get its data from?
The survey-mark data used in Markline is sourced from the NOAA National Geodetic Survey and is in the public domain. The official source is geodesy.noaa.gov.
