Comparison

AccessRuler vs RTAB

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

AccessRuler

Features
Read full description

Disclaimer: This app requires a Leica Distance Laser Meter. In celebration of the 40th anniversary of the Americans with Disabilities Act, the R2D2 Center has released the AccessRatings for Buildings MiniTools apps that include AccessRuler, AccessSlope and AccessSound. AccessRuler can be downloaded on iPhones or iPads. AccessRuler is an app that measures distances for accessibility purposes. This tool uses a Leica Disto Meter that connects to an iPad or iPhone via Bluetooth and automatically imports the measurement from the ruler into the app. The app allows users to add comments, save their measurements to a list within the app, and export the measurements through email.

About

RTAB

This utility app enables real-time 3D scanning and mapping of environments using LiDAR or RGB-D sensors. It features online loop closure detection and map optimization for immediate feedback, with export options for various 3D formats.

Highlights
  • Online 3D scanning and mapping
  • Loop closure detection and map correction
  • Save maps in DB format
  • Export in PLY, LAS, or OBJ
  • Multi-session mapping
  • AR/VR visualization mode
Read full description

RTAB-Map (Real-Time Appearance-Based Mapping) is an Open Source LiDAR / RGB-D / Stereo Graph-Based SLAM (Simultaneous Localization and Mapping) approach based on an online incremental appearance-based loop closure detector. The loop closure detector uses a bag-of-words approach to determinate how likely a new image comes from a previous location or a new location. When a loop closure hypothesis is accepted, a new constraint is added to the map's graph, then a graph optimizer minimizes the errors in the map in real-time. An optional memory management approach can be used to limit the number of locations used for loop closure detection and graph optimization, so that real-time constraints on large-scale environnements are always respected. ARKit's visual inertial odometry (VIO) is used as the SLAM front-end for RTAB-Map (the SLAM back-end). * Note that unlike other scanning apps that optimize the map only after mapping, with RTAB-Map you get loop closure detection and map optimization online so you can have a live feedback to know when you have enough constraints in the map for good global optimization before stopping the scan. *** 3D reconstruction available only with LiDAR sensor. Features: * Online 3D scanning/mapping of the environment. * Online loop closure detection and map correction. * Save in DB format (RTAB-Map desktop and rtabmap_ros format). * Export in PLY, LAS or OBJ. * Multi-session mapping (save and continue later). * Use Apriltags to help finding loop closures in textureless environments. * Mixed AR/VR First-Person in visualization mode. * Raw ARKit data recording (up to 60 Hz!), useful to record long sessions without comprising battery life.

Screenshots

AccessRuler4 screens
RTAB3 screens

Verdict

The call

The clearest difference is price: RTAB at Free against AccessRuler's $0.99. RTAB also leads on update cadence (every 4 months vs every 28 months). AccessRuler's advantage is iOS requirement (12.0 vs 14.3). On ads, in-app purchases and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

RTAB is free to download; AccessRuler costs $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

AccessRuler ships an update every 28 months, RTAB every 4 months. The most recent releases landed on September 19, 2026 and September 23, 2026 respectively.

Scorecard3 real differences · 7 level
AccessRuler versus RTAB: the parameters behind the verdict, then further details
ParameterAccessRulerRTAB
Price$0.99Free — better
Rating—4.8 (39 ratings) — better
Positive reviews—100.0% of reviews
Number of ratings—39 — better
Update frequencyEvery 28 monthsEvery 4 months — better
AdsNoNo
In-app purchasesNoNo
Monetization—Free
DevicesiPhone, iPodiPhone, iPad, iPod — better
Requires iOS12.0 — better14.3
Further details — not scored
Size4 MB19 MB
Age rating4+4+
DeveloperUniversity of Wisconsin–MilwaukeeMathieu Labbe

In-app purchases

None

AccessRuler

No in-app purchases

None

RTAB

No in-app purchases

Questions

Is AccessRuler free?
AccessRuler costs $0.99, with no in-app purchases.
Is RTAB free?
RTAB is free to download, with no in-app purchases.
Do AccessRuler or RTAB have ads?
Neither AccessRuler nor RTAB shows ads.
Which is updated more often, AccessRuler or RTAB?
AccessRuler ships an update every 28 months, and RTAB every 4 months. Most recently, AccessRuler was updated on September 19, 2026 and RTAB on September 23, 2026.

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