Comparison

FaultKin Mobile vs Rock & Crystal Identifier

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

Head to head
About

FaultKin Mobile

This app allows geologists to collect, visualize, and analyze fault slip data directly from their mobile device. It offers both automatic data entry using device orientation and manual input options, with features for grouping data and performing basic calculations.

Highlights
  • Automatic data entry via device orientation
  • Manual data entry via stereonet or text fields
  • Group faults with custom tags
  • Perform basic calculations (rotations, unfolding)
  • Plot P and T axes, moment tensor axes
  • View plots from any orientation
  • Stamp entries with time, date, and location
Features
Read full description

FaultKin Mobile is designed to help you collect, visualize, and analyze fault slip data on the go. It is a companion to my FaultKin program for desktop computers, but it can also be used to measure faults on the outcrop. The app has the following features: - Provide automatic data entry as a geologist's compass by reading the iOS device orientation and converting it to strike and dip of planes and/or trend and plunge of lines. - Provide manual data entry via either tapping and dragging on the stereonet or by typing values into text fields. - Groups of faults can be assigned different tags. You will probably want to do this based on location or other criteria. For example, you may want to have a tag labeled "Corral Quemado-Older" and anther "Corral Quemado-Younger". - Carry out basic calculations such as: rotations about any axis, unfolding faults around local bedding, or measure angles between lines and between planes. - Plot P and T axes, (unweighted) moment tensor axes, P-T dihedra, fault plane solutions, and contour P and T axes. - View the plots from any orientation, not just looking straight down into the lower hemisphere - Stamp each entry with time date and, if enabled by the user, location. See the location of a datum in the iOS Maps program - Provide basic input and output of data using standard iOS conventions - Work on both iPhones or iPads, both in portrait mode only. The desktop version of FaultKin will soon be updated so that it can read and write FaultKin Mobile files, which are simple tab separated text files. Use it at your own risk. In particular, recall that your iOS device is very sensitive to magnetic fields and the compass bearings can easily be off by 10-20°! This program should not be used as a sole source of navigation data. The author assumes no responsibility for incorrect results, unanticipated behaviors, loss resulting from results provided by the program, or any other anticipated or unanticipated event related to the program.

About

Rock & Crystal Identifier

Identify rocks, minerals, crystals, and gems instantly by taking a photo. Access a comprehensive database with detailed information, educational content, and fun facts about geology and gemology. Perfect for hobbyists, students, and anyone curious about the natural world.

Highlights
  • Instant photo identification
  • Comprehensive rock and gem database
  • Detailed specimen information
  • Educational geology content
  • User-friendly interface
Features
Read full description

Uncover the hidden treasures of the Earth with Rock & Crystal Identifier: Gem! Whether you're a budding geologist, a student, or just curious about the natural world, our app makes identifying rocks, minerals, crystals, and gems effortless and exciting. Simply take a photo, and our advanced AI technology will analyze its features to provide you with detailed information, including its name, type, and properties. Key Features of Rock & Crystal Identifier: Gem Instant Identification: Snap a photo and get instant results with high accuracy. Comprehensive Database: Access a vast database of rocks, minerals, crystals, and gems. Detailed Descriptions: Learn about each specimen’s composition, formation, and uses. Educational Content: Dive deeper with articles and fun facts about geology and gemology. User-friendly Interface: Enjoy a seamless experience with our intuitive design. Perfect for hobbyists, educators, and professionals, Rock & Crystal Identifier: Gem by Photo transforms your smartphone into a powerful tool for exploring the natural world. Start your geological adventure today and uncover the secrets of the Earth with every photo you take! Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

FaultKin Mobile4 screens
Rock & Crystal Identifier4 screens

Verdict

The call

The clearest difference is in-app purchases: FaultKin Mobile at none against Rock & Crystal Identifier's 3. FaultKin Mobile also leads on rating (5.0 vs 4.8) and update cadence (every 2 months vs every 3 months). Rock & Crystal Identifier's advantage is ratings volume (29 vs 2). On price, ads 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. Rock & Crystal Identifier sells 3 in-app purchases, starting at $6.99 per 7 days. FaultKin Mobile asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

FaultKin Mobile holds the better App Store score, 5.0 against 4.8. That said, the two scores are not equally well evidenced: Rock & Crystal Identifier has 29 ratings behind it against 2, so its average is the more settled of the two.

UpkeepUpdate frequency

FaultKin Mobile ships an update every 2 months, Rock & Crystal Identifier every 3 months. The most recent releases landed on November 2, 2026 and November 5, 2026 respectively.

Scorecard6 real differences · 4 level
FaultKin Mobile versus Rock & Crystal Identifier: the parameters behind the verdict, then further details
ParameterFaultKin MobileRock & Crystal Identifier
PriceFreeFree
Rating5.0 (2 ratings) — better4.8 (29 ratings)
Positive reviews—0.0% of reviews
Number of ratings229 — better
Update frequencyEvery 2 months — betterEvery 3 months
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree — betterFreemium
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS11.0 — better15.6
Further details — not scored
Size28 MB106 MB
Age rating4+4+
DeveloperRichard AllmendingerBhavinkumar Satashiya

Customer experience

FaultKin Mobile

All ratings2 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

Rock & Crystal Identifier

All ratings29 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews2 reviews
Positive0.0%
Neutral0.0%
Negative100.0%

In-app purchases

None

FaultKin Mobile

No in-app purchases

3 purchases

Rock & Crystal Identifier

Subscriptions3
  • Weekly Subscription$6.997 Days
  • Monthly Subscription$17.991 Month
  • Yearly Subscription$49.991 Year

Questions

Is FaultKin Mobile free?
FaultKin Mobile is free to download, with no in-app purchases.
Is Rock & Crystal Identifier free?
Rock & Crystal Identifier is free to download, with in-app purchases available.
Which has better reviews, FaultKin Mobile or Rock & Crystal Identifier?
FaultKin Mobile is rated higher. FaultKin Mobile averages 5.0 out of 5 from 2 ratings, while Rock & Crystal Identifier averages 4.8 from 29 ratings.
Do FaultKin Mobile or Rock & Crystal Identifier have ads?
Neither FaultKin Mobile nor Rock & Crystal Identifier shows ads.
Which is updated more often, FaultKin Mobile or Rock & Crystal Identifier?
FaultKin Mobile ships an update every 2 months, and Rock & Crystal Identifier every 3 months. Most recently, FaultKin Mobile was updated on November 2, 2026 and Rock & Crystal Identifier on November 5, 2026.

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