Comparison

Video tachometer vs Strobe Light

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

Head to head
About

Video tachometer

This app uses slow-motion video to create a strobe light effect, allowing you to measure rotational speeds. It records video with detailed information like frame rate and exposure, and offers customizable text overlays.

Highlights
  • Strobe light effect simulation
  • Rotational speed measurement (RPM/Hz)
  • Slow-motion video recording
  • Customizable text overlays on video
  • Adjustable frame rate and exposure
  • Records 4K video (if supported)
Read full description

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)). If the exposure time is reduced, the image will increase in clarity, but brightness will lower. To increase the brightness, you need to raise the camera's light sensitivity (ISO), but then the amount of noise increases. You also need to manually adjust the focus of the camera. The app can record video. The video format depends on the selected format in the app settings. If your iPhone supports 4K video format (3840x2160), then you can record 4K video at the frame rate supported by your iPhone. Text with important information is added to the frames of the recorded video: the selected frame rate, exposure duration, ISO, time stamp, time difference between the current and previous frames (Tcurr. − Tprev.), the sequence number of the frame in the recorded video. If you want any other information to be added, then let me know. You can choose to add only part of this information, and you can choose a different text color. You also have the option of not adding any information. You can change the information that is added and the color of the text while recording a video. At high frame rates, frames that do not have time to be processed may be discarded. This does not affect subsequent frames and can be controlled using the time difference between the current frame and the previous frame (Tcurr. − Tprev.). Dropping frames affects the video frame rate displayed in the "Photos" app. But the time interval between frames that were taken one after another and were not discarded will correspond to the selected frame rate. Frames may be dropped even when shooting slow motion video using the "Camera" app. You can check this by looking at the frame rate for slow motion video in the "Photos" app. Video containing the app's interface can be captured using the iOS "Screen Recording" function. The app can take a photo with the measurement result, date, and time written on the photo. The exposure time and ISO settings will be saved in the photo's metadata. To take a photo that shows the app interface, tap the "Pause" button and take a screenshot. It is possible to choose a video format that has the best quality, but has a significantly lower maximum frame rate. The difference between the formats is clearly visible only when using the digital zoom. Also, when using a format with better quality, the Rolling Shutter effect is stronger. Therefore, the best quality format can be used at speeds less than about 2000 rpm. You can turn on hints for easier observation of changes in rotation speed. Hints show how to change the frame rate (decrease or increase) depending on the direction of rotation of the mark. The hints are selected manually, but then you do not need to remember this information. The hints are relevant for frequencies close to the rotation frequency. If the direction of rotation of the impeller is known, hints can be selected in advance. The arrow showing the direction of rotation of the impeller must correspond to the "+" button. The video tachometer measures the rotational speed in exactly the same way a stroboscopic tachometer would.

About

Strobe Light

This application transforms your smartphone into a digital tachometer using its flashlight. It measures the rotational speed (RPM) of objects by flashing light at them, making them appear stationary when the flash rate matches their speed. Save readings and use it for mechanics, education, or industrial checks.

Highlights
  • Measures RPM of rotating objects
  • Adjustable strobe speed (1-10,000 RPM)
  • Quick adjustment buttons (+/- increments)
  • Flash sync for accuracy
  • Save and review RPM data
  • Works in low light conditions
Features
Read full description

Strobe Light - RPM turns your phone into a powerful tool for measuring the speed of rotating objects. The app works like a digital tachometer and offers two measurement modes: Strobe Light and Camera. You can measure the RPM of fans, motors, wheels, and other rotating devices without touching them. In both modes, the same stroboscopic principle is used. When the flash rate or camera frame rate matches the speed of the object, it creates the illusion that the object is standing still. This helps you visually determine the exact rotational speed of the object with high accuracy. Strobe Light Mode Using your phone's flashlight, this mode flashes light at the object in a specific pattern. It works best in a dark or low-light environment and is ideal when you want a quick RPM reading with the built-in flashlight. How to Use (Strobe Light): Mark the rotating object with something visible (a sticker or tape works well). Point your phone's flashlight toward the object. Turn on the strobe using the power button. Adjust the strobe speed using the + and - buttons until the object looks still. The RPM shown on the screen is the object's rotation speed. You can save the reading for later reference. Camera Mode Camera mode uses your phone's camera to show a live preview at a set frame rate (FPM — Frames Per Minute). When the frame rate matches the object's RPM, the rotating object appears frozen on screen. This mode is useful in well-lit conditions when you want to see the object clearly while tuning the speed. How to Use (Camera): Open Camera mode from the home screen and allow camera permission. Point the camera at the rotating object. Adjust the frame rate using the + and - buttons until the object looks still. The value shown on the screen is the object's RPM. Use the flash button if you need extra light in darker areas. Save or reset your reading anytime from the bottom buttons. Where It's Useful: Mechanics: Test fans, engines, or motors by measuring RPM. Education: Ideal for physics experiments that require RPM measurements. Industrial Use: Check the condition of rotating machinery. Calibration: Ensure rotating devices are running at the correct speed. Maintenance: Compare readings over time using saved history. Key Features: Two Measurement Modes: Choose Strobe Light or Camera from the home screen based on your environment and preference. Adjustable Strobe Speed: Set the strobe from 1 to 10,000 RPM for accurate measurements. Camera Frame Rate Control: Set camera preview from 30 to 14,400 FPM for precise visual tuning. Quick Adjustment Buttons: Easily change the speed with buttons for +1, +10, +50, or +100 RPM increments in both modes. Flash Sync (Strobe Light): Ensures the light flashes at the correct frequency for accurate RPM readings. Built-in Camera Flash (Camera Mode): Toggle the flash on or off for better visibility in low light. Save and Reset: Save current RPM readings with a custom title or reset to default anytime. History Tracking: Save and review your RPM data anytime for easy access from the menu. Works in Different Lighting: Strobe Light works best in the dark; Camera mode works well in normal and low-light conditions. Simple and Energy-Efficient: The app's interface is easy to use and designed to be practical for everyday measurements. Visual Tachometer: Acts just like a real tachometer using visual strobe techniques with your phone's flashlight or camera. Strobe Light - RPM makes it simple to measure RPM without any special tools or equipment. Whether you prefer the classic flashlight strobe method or the new live camera preview, this app gives you flexible and accurate RPM measurement in one place. Perfect for mechanics, hobbyists, students, and professionals alike. Contact us at: zsmapps2024@gmail.com Terms of use: Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

Video tachometer4 screens
Strobe Light3 screens

Verdict

The call

The clearest difference is review sentiment: Video tachometer at 85% against Strobe Light's 0%. Video tachometer also leads on rating (4.6 vs 2.0) and ads (none vs shown). Strobe Light's advantage is in-app purchases (none vs 1). On price, device support and iOS requirement 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. Video tachometer sells 1 one-off in-app purchase. Strobe Light asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

Video tachometer holds the better App Store score, 4.6 against 2.0. That said, the two scores are not equally well evidenced: Video tachometer has 84 ratings behind it against 1, so its average is the more settled of the two. Written reviews point the same way: 85% of Video tachometer's written reviews are positive against 0% of Strobe Light's.

UpkeepUpdate frequency

Video tachometer ships an update every 3 months, Strobe Light every 7 months. The most recent releases landed on September 26, 2026 and September 22, 2026 respectively.

Scorecard7 real differences · 3 level
Video tachometer versus Strobe Light: the parameters behind the verdict, then further details
ParameterVideo tachometerStrobe Light
PriceFreeFree
Rating4.6 (84 ratings) — better2.0 (1 ratings)
Positive reviews84.9% of reviews — better0.0% of reviews
Number of ratings84 — better1
Update frequencyEvery 3 months — betterEvery 7 months
AdsNo — betterYes
In-app purchasesYesNo — better
MonetizationFree with in-app purchasesAd-supported — better
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS15.615.0 — better
Further details — not scored
Size5 MB25 MB
Age rating4+4+
DeveloperDmitriy KharutskiyZain Saeed Mughal

Customer experience

Video tachometer

All ratings84 ratings
Positive90.5%
Neutral0.0%
Negative9.5%
Written reviews53 reviews
Positive84.9%
Neutral1.9%
Negative13.2%

Strobe Light

All ratings1 ratings
Positive0.0%
Neutral0.0%
Negative100.0%
Written reviews1 reviews
Positive0.0%
Neutral0.0%
Negative100.0%

Bugs and requests

Video tachometer

Reported bugs

3 issues
  • Does not read anything
  • Pop-ups for paid features
  • Interface visible in screen recording

Requested features

4 requests
  • Ability to record video
  • Slow phase shift mode
  • Improved UI for initial setup
  • Long press for gradual increment/decrement

Strobe Light

Not enough reviews yet to summarise bugs or requests.

In-app purchases

1 purchases

Video tachometer

One-time1
  • Full version$2.99
None

Strobe Light

No in-app purchases

Questions

Is Video tachometer free?
Video tachometer is free to download, with in-app purchases available.
Is Strobe Light free?
Strobe Light is free to download, with no in-app purchases.
Which has better reviews, Video tachometer or Strobe Light?
Video tachometer is rated higher. Video tachometer averages 4.6 out of 5 from 84 ratings, while Strobe Light averages 2.0 from 1 ratings.
Do Video tachometer or Strobe Light have ads?
Strobe Light shows ads; Video tachometer does not.
Which is updated more often, Video tachometer or Strobe Light?
Video tachometer ships an update every 3 months, and Strobe Light every 7 months. Most recently, Video tachometer was updated on September 26, 2026 and Strobe Light on September 22, 2026.

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