Comparison

Ruler with Caliper, Protractor vs RSA Lab

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

Head to head
About

Ruler with Caliper, Protractor

This app transforms your device into a precise digital measuring tool. It offers accurate measurements for various objects and distances using your camera, with multiple units and offline functionality.

Highlights
  • Accurate measurements via camera
  • Measure small objects to large distances
  • User-friendly interface
  • Multiple measurement units (inches, cm)
  • Virtual ruler on screen
  • Save and share measurements
  • Offline accessibility
Features
Read full description

# Ruler โ€“ Digital Ruler & Tape Measure Turn your smartphone into a precise measuring tool with **Ruler โ€“ Digital Ruler & Tape Measure**. Whether you're measuring small objects, checking angles, finding distances, or ensuring a perfectly level surface, this all-in-one toolkit provides everything you need in one easy-to-use app. Perfect for students, engineers, architects, designers, DIY enthusiasts, woodworkers, and everyday use. ## Features **Digital Ruler** Measure the length and width of objects directly on your phone screen with accurate calibration. **Tape Measure** Quickly measure objects using your device with an easy-to-read digital measuring interface. **Caliper** Measure thickness, internal diameter, external diameter, and depth with precision. Great for mechanical parts, jewellery, hardware, and engineering tasks. **Pinpoint Measurement** Measure the exact distance between two fingers on your screen for quick and convenient measurements. **Spirit Level** Check whether surfaces are perfectly horizontal or vertical using your phone's built-in sensors. Ideal for hanging pictures, installing shelves, and DIY projects. **Protractor** Measure and draw angles in degrees with an accurate digital protractor for school, construction, and design work. **Calibration Tool** Calibrate the ruler to your device for reliable and precise measurements across different screen sizes. ## Why Choose Ruler? * Fast and easy to use * Accurate digital measurements * Multiple measuring tools in one app * Clean and intuitive interface * Suitable for home, school, office, workshop, and construction * Works on most iOS devices Whether you're measuring furniture, checking angles, calculating dimensions, or levelling surfaces, **Ruler โ€“ Digital Ruler & Tape Measure** gives you the essential tools you need wherever you go. Download now and carry a complete measuring toolkit in your pocket. Privacy Policy : https://forms.gle/dnBUgnpqw4AREio97 Terms of Use : https://forms.gle/2uy2JqJa2JjkTZpo8

About

RSA Lab

Features
Read full description

You can use RSA Lab to generate RSA keys, decrypt encrypted messages and encrypt messages.ย  You can also store and name your RSA private and public keys in RSA Lab. All data in RSA Lab is synchronized on the iCloud.

Screenshots

Ruler with Caliper, Protractor4 screens
RSA Lab3 screens

Verdict

The call

The clearest difference is in-app purchases: RSA Lab at none against Ruler with Caliper, Protractor's 3. RSA Lab also leads on ads (none vs shown). On price, update cadence, device support and iOS requirement there is nothing between them.

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

CostPrice ยท In-app purchases ยท Ads ยท Monetization

Both are free to download. Ruler with Caliper, Protractor sells 3 in-app purchases, starting at $3.99 per 7 days. RSA Lab asks for nothing beyond the download.

UpkeepUpdate frequency

Ruler with Caliper, Protractor ships an update every 28 months, RSA Lab every 42 months. The most recent releases landed on November 2, 2026 and November 3, 2026 respectively.

Scorecard2 real differences ยท 6 level
Ruler with Caliper, Protractor versus RSA Lab: the parameters behind the verdict, then further details
ParameterRuler with Caliper, ProtractorRSA Lab
PriceFreeFree
Positive reviews0.0% of reviewsโ€”
Update frequencyEvery 28 months โ€” betterEvery 42 months
AdsYesNo โ€” better
In-app purchasesYesNo โ€” better
MonetizationFree with in-app purchasesโ€”
DevicesiPhone, iPadiPhone, iPad
Requires iOS16.0 โ€” better16.2
Further details โ€” not scored
Size6 MB1 MB
Age rating4+4+
DeveloperBhavinkumar Satashiyaๆจๆด‹ ๅ†ฏ

In-app purchases

3 purchases

Ruler with Caliper, Protractor

Subscriptions2
  • Weekly$3.997 Days
  • Yearly$39.991 Year
One-time1
  • Lifetime$49.99
None

RSA Lab

No in-app purchases

Questions

Is Ruler with Caliper, Protractor free?
Ruler with Caliper, Protractor is free to download, with in-app purchases available.
Is RSA Lab free?
RSA Lab is free to download, with no in-app purchases.
Do Ruler with Caliper, Protractor or RSA Lab have ads?
Ruler with Caliper, Protractor shows ads; RSA Lab does not.
Which is updated more often, Ruler with Caliper, Protractor or RSA Lab?
Ruler with Caliper, Protractor ships an update every 28 months, and RSA Lab every 42 months. Most recently, Ruler with Caliper, Protractor was updated on November 2, 2026 and RSA Lab on November 3, 2026.

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