Comparison

Image Ruler vs CAPN

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

Head to head
About

Image Ruler

This app allows you to measure objects directly on photos. Simply take a picture, mark a known object for reference, and then draw measurements on other items within the same image. It supports both metric and imperial units and offers intuitive editing tools.

Highlights
  • Measure objects on photos
  • Use a known object as a reference
  • Supports metric and imperial units
  • Intuitive editing interface
  • Organize photos easily
  • Zoom for precision
Features
Read full description

Measure anything in any photo. Take a photo or import one from your library, place a reference object you already know the size of, and instantly calculate real-world measurements — lengths, angles, and areas — directly on the image. How it works Set a reference line on a known object in your photo. From there, every measurement you draw is automatically calculated in real scale. What you can measure Ruler — measure distances and lengths Arrow — annotate with directional measurements Angle — measure the angle between any two lines Area — tap points to outline a surface and calculate its area Built for precision Works entirely offline — no internet required Metric and imperial units Pinch to zoom for precise point placement Undo and redo any change Hide or show your reference line at any time Tips for accurate results For best accuracy, make sure your reference object and the object you're measuring are in the same plane, and that the camera was parallel to both when the photo was taken. Perspective distortion affects results. Measurements are estimates based on the reference you provide.

About

CAPN

This app connects users with trained community members for assistance in unsafe situations. It provides a network of trusted individuals ready to help when you feel vulnerable.

Highlights
  • Community-assisted protection
  • Trained and trusted members
  • Local assistance
  • Safety network
  • Compassionate support
Features
Read full description

CAPN (Community Assisted Protection Network) is a mobile application that allows its users to summon a trained, trusted, and compassionate member of their local community to assist them in situations where they feel unsafe.

Screenshots

Image Ruler4 screens
CAPN4 screens

Verdict

The call

The clearest difference is rating: CAPN at 5.0 against Image Ruler's 1.5. CAPN also leads on in-app purchases (none vs 7) and update cadence (every 2 days vs every 3 weeks). Image Ruler's advantage is ratings volume (44 vs 3). On price, ads, monetization model 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

Both are free to download. Image Ruler sells 5 one-off in-app purchases. CAPN asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

CAPN holds the better App Store score, 5.0 against 1.5. That said, the two scores are not equally well evidenced: Image Ruler has 44 ratings behind it against 3, so its average is the more settled of the two.

UpkeepUpdate frequency

Image Ruler ships an update every 3 weeks, CAPN every 2 days. The most recent releases landed on October 4, 2026 and October 15, 2026 respectively.

Scorecard4 real differences · 6 level
Image Ruler versus CAPN: the parameters behind the verdict, then further details
ParameterImage RulerCAPN
PriceFreeFree
Rating1.5 (44 ratings)5.0 (3 ratings) — better
Positive reviews17.6% of reviews—
Number of ratings44 — better3
Update frequencyEvery 3 weeksEvery 2 days — better
AdsNoNo
In-app purchasesYesNo — better
MonetizationFreeFree
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS15.115.1
Further details — not scored
Size47 MB47 MB
Age rating4+4+
DeveloperMartin SchurmannCAPN LLC

Customer experience

Image Ruler

All ratings42 ratings
Positive14.3%
Neutral0.0%
Negative85.7%
Written reviews17 reviews
Positive17.6%
Neutral0.0%
Negative82.4%

CAPN

All ratings3 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

5 purchases

Image Ruler

One-time5
  • imageRulerPro$0.99
  • Small Tip2 variants$0.99
  • Medium Tip2 variants$2.99
Show 2 more
  • Big Tip$4.99
  • Big tip$4.99
None

CAPN

No in-app purchases

Questions

Is Image Ruler free?
Image Ruler is free to download, with in-app purchases available.
Is CAPN free?
CAPN is free to download, with no in-app purchases.
Which has better reviews, Image Ruler or CAPN?
CAPN is rated higher. Image Ruler averages 1.5 out of 5 from 44 ratings, while CAPN averages 5.0 from 3 ratings.
Do Image Ruler or CAPN have ads?
Neither Image Ruler nor CAPN shows ads.
Which is updated more often, Image Ruler or CAPN?
Image Ruler ships an update every 3 weeks, and CAPN every 2 days. Most recently, Image Ruler was updated on October 4, 2026 and CAPN on October 15, 2026.

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