App Store
Version 2.1.10 · 2026-08-22
• The phase shift of a moving object in an image when the image is made still. Touch and hold.
Too little checked to say Store information only. We haven’t analysed this app or read its reviews yet.
Not yet tested.
The store currently lists version 2.1.10, updated 2026-08-22.








Store screenshots supplied by the developer.
When the frame rate of a video matches the speed of a particular part, the effect is the same as using a strobe light. In the video, that part freezes.
Since the frame rate of a video can be adjusted, this effect can be used to determine the rotational speed of a part.
The smartphone must support slow-motion video recording (filming at a high frame rate). This is the case for all smartphones starting with iPhone 5S. The range is as follows:
• 0.5—240 Hz (30—14400 RPM), for all phones from iPhone 6 onward
• 0.5—120 Hz (30—7200 RPM), for iPhone 5S
THE HERTZ (Hz) VALUE IS MORE ACCURATE THAN THE REVOLUTIONS PER MINUTE (RPM) VALUE, SINCE REVOLUTIONS PER MINUTE ARE CALCULATED FROM HERTZ AND ROUNDING IS DONE.
To get a clear image, good lighting is important. The clarity of the image is controlled by the exposure of the video (exposure time and light sensitivity (ISO)).…
From the developer’s store description.
For developers and the curious
The evidence, sources, measurements and versions behind every label above.
No review analysis published for this app.
“Not assessed” means we could not measure it. It is never a zero and never a pass.
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.
Supporting measurements: not a complete list of possible harms or positives. Measurement vocabulary 1.4 · how these are measured
Not yet tested. No analysis has been run for this app, so there is no version or date to report.
Each store’s release notes, as the developer wrote them. They are the developer’s words, not ours.
• The phase shift of a moving object in an image when the image is made still. Touch and hold.
video-tachometerWhat the stores publish. Store ratings are the stores’ numbers, not Appworthy’s, and are never averaged across stores.
From the store listing. Billing terms are read from each purchase’s name — the stores don’t publish them — so treat them as a strong hint, not a disclosure.
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.
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.