Appworthy
App Store
Version 1.0 · 2026-07-31
No release notes were provided for this version.
Store ratingNo rating
Price$1.99Listed price
Age4+Store age rating
Size3 MBiPhone download
CategoryProductivity
DeveloperC&S Industries, LLC
What we found
Full reportToo little checked to say Store information only. We haven’t analysed this app or read its reviews yet.
Money
- $1.99 to download.
Not yet tested.
The store currently lists version 1.0, updated 2026-07-31.
Preview
Store screenshots supplied by the developer.
About this app
Point your phone at a running engine and read its RPM instantly — no OBD adapter, no clip-on inductive sensor, no wiring. RPMCalc listens through your microphone and calculates engine speed straight from the sound of the exhaust or the engine itself.
HOW IT WORKS
Every engine's exhaust note has a fundamental firing frequency set by its cylinder count, stroke cycle, and RPM. RPMCalc analyzes that frequency in real time and converts it to a live RPM reading — accurate to the nearest 1 RPM on the digital readout, with a classic analog tachometer dial for an at-a-glance feel.
BUILT FOR ANY ENGINE
- Set any cylinder count from 1 to 12
- Choose 2-stroke or 4-stroke cycle
- Works on cars, motorcycles, lawn mowers, generators, chainsaws, go-karts, boats, and other small engines
WORK ALONE, HANDS-FREE
Diagnosing an engine is usually a two-person job — one to rev it, one to watch the gauge.…
From the developer’s store description.
For developers and the curious
The full report
The evidence, sources, measurements and versions behind every label above.
Findings and evidence
Not yet tested. No analysis has been published for this app. A missing label is not a clean bill of health.
What reviewers report
No review analysis published for this app.
Measurements
“Not assessed” means we could not measure it. It is never a zero and never a pass.
From store data and reviews
Developer replies to reviews
Not assessed
Fewer than 50 reviews scanned — too few to state a rate
Price in the store description
The store description doesn’t list prices (most don’t)
Cancelling, in the store description
The store description doesn’t say how to cancel (most don’t)
Themes reported by reviewers
Not assessed
This app's reviews have not been assessed yet
Five-star share of ratings
Not assessed
No rating histogram has been captured for this app
In the app package we scanned
No package has been scanned for this app, so nothing is published about what it ships. That is an absence of evidence, not a finding.
Sensitive permissions
Not assessed
No package has been scanned for this app
Analytics or tracking SDKs in the scanned package
Not assessed
No package has been scanned for this app
Advertising SDKs in the scanned package
Not assessed
No package has been scanned for this app
How we know
Supporting measurements: not a complete list of possible harms or positives. Measurement vocabulary 1.4 · how these are measured
Versions and dates analysed
Not yet tested. No analysis has been run for this app, so there is no version or date to report.
Store update history
Each store’s release notes, as the developer wrote them. They are the developer’s words, not ours.
Assessment record
- Status
- Not yet tested
- App identifier
myrpmcalc- Sources used
- None recorded
- Reviews read
- None recorded
- Package examined
- No package scan
- Human inspection
- Not completed
How we know
- Measurement vocabulary
- 1.4
Store facts
What the stores publish. Store ratings are the stores’ numbers, not Appworthy’s, and are never averaged across stores.
App Store
- Store rating
- Not supplied
- Version
- 1.0
- Updated
- 31 Jul 2026
- Price
- $1.99
- Age rating
- 4+
- Size
- 3 MB
- Developer
- C&S Industries, LLC
- Category
- Productivity
- Listing price
- $1.99
No itemized purchase list is available for this listing.
Method and limits
What a missing label means
Not yet tested. No analysis has been published for this app, so there is no method to describe for it yet. A missing label is not a clean bill of health: it means nothing has been read, not that nothing is wrong.
Limits of this report
- A package scan is static. It identifies code and text in one Android build. It does not measure a live ad session, test a deletion request, or count the steps needed to cancel.
- Reviews keep their sample. A review-only charge shows distinct reviewers, the share and the sample size, and is published only once it clears that label’s published threshold. Calibration labels are machine-drafted and not yet confirmed by a person.
- Not assessed is a state. It is never a zero and never a pass.
- A missing label is not a clean bill of health. It means the evidence did not support one, not that the app is problem-free.
Not yet human-reviewed. A human review gives an app hands-on, recorded measurements. None has been run for this app. Hands-on inspections are not yet open.
Request a correction
Write to [email protected], or use the form. Name the finding, the app version and the evidence that needs correcting. Factual corrections are free and never depend on buying anything.