Mastlens
One-click tower closeouts
Only for iPhone
Free · Designed for iPhone. Not verified for macOS.
iPhone
Capture GPS and time-stamped job-site photos, run structured checklists, and keep tower closeout documentation moving — even where there's no signal.
Description
Mastlens is the field documentation app for telecom tower crews. Capture the proof your closeout package needs — right at the site, even with zero signal — and let the paperwork build itself while you work.
BUILT FOR TOWER WORK
• Every photo is automatically stamped with GPS coordinates and time, so your documentation holds up
• Structured checklists mirror your company's closeout requirements — no more guessing which shots are missing
• See exactly what's done and what's left before you leave the site, and skip the costly return trips
WORKS OFFLINE
Tower sites rarely have good coverage. Mastlens stores photos and checklist progress on the device and syncs automatically when you're back in range.
FROM SITE TO CLOSEOUT
Everything you capture syncs to the Mastlens platform, where your back office assembles polished, client-ready closeout packages — organized by project, checklist, and section.
FOR TEAMS
• Projects and checklists assigned to your crew show up ready to work
• Managers see field progress as it syncs
• Role-based access keeps everyone in their lane
Mastlens is built for telecom tower installation and maintenance companies. An account provided by your company is required to sign in — ask your Mastlens administrator for an invitation.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
Certifications beyond Safety LMS
• CPR cards, OSHA cards and any other certificates your company has uploaded now appear in the app alongside the ones synced from Safety LMS, with the same expiry marks. Uploading and approving stay on the web app.
• A new filter at the top of Certifications switches between All sources, Safety LMS and Other, so you can look at one feed at a time.
• Search your crew's certifications by name, email address or certificate number — useful when you are standing at the gate confirming that one person is current.
Marking a field complete is now your call
• Taking a photo no longer completes the field. It stays grey until you tap the circle, so "done" means somebody actually checked it. Tap again to un-mark.
• Works with no signal: the tap sticks immediately and syncs when you are back on, in the right order behind any photos still uploading.
Camera
• Pinch-to-zoom actually works. Any pinch used to shoot straight to maximum or minimum zoom, which made it useless for framing a shot. The zoom now follows your fingers, the × you are on shows while you pinch, and releasing near 0.5×, 1× or 3× snaps to it.
• Turn the shutter sound and the camera haptics off, under Settings → Capture. Both are on by default. The shutter sound is a request rather than a guarantee — iOS and some jurisdictions force it at the system level.
Fix your name from the app
• Tap the pencil beside your name on Profile to change your first and last name, and admins can correct anyone's the same way from that person's page under More → Users. This one needs a signal — unlike photos and field sign-offs, a name change is not queued for later.
The developer, Checksum Works 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 Linked to You
The following data may be collected and linked to your identity:
- Contact Info
- Identifiers
Data Not Linked to You
The following data may be collected but it is not linked to your identity:
- Location
- User Content
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Checksum Works LLC
- Size
- 49.9 MB
- Category
- Business
- Compatibility
Requires iOS 15.1 or later.
- iPhone
Requires iOS 15.1 or later. - iPod touch
Requires iOS 15.1 or later. - Mac
Requires macOS 12.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- Contains
User-Generated Content
- Copyright
- © 2026 Checksum Works LLC
