4 Best iPhone Tachometer App

"This post includes affiliate links for which I may make a small commission at no extra cost to you should you make a purchase."

Download the Best iPhone Tachometer App on the Apple Store by clicking this Button

If you are looking for the Best iPhone Tachometer App to download for free, look no further.

Our expert panel of reviewers has tested dozens of apps and we have compiled a list of the 4 Best iPhone Tachometer App that passed our tests.

Check out our list of the 4 Best iPhone Tachometer App, tried and tested by our expert reviewers.

4 Best iPhone Tachometer App

1. Engine RPM

Download the App on the Apple Store by clicking this Button
“This app measures the RPM of an engine by analyzing the sound it makes. It uses advanced signal processing algorithms to measure the pitch of the sound and display and log the calculated RPM.

This app will not work if the engine sounds are muffled or unstable or combined with too much other noise. The engine sound must be clear and stable and sound like a single tone. Other sounds can also prevent the engine sound from being analyzed.

The software is configurable for 2-cycle and 4-cycle engines and includes a generic configuration for unusual cases, such as a reduction gear. The normal RPM range is 400 to 90,000 RPM, although much lower RPMs can be measured using the manual RPM matching option.

A detailed manual is available from our support webpage.”

2. Strobe Light Tachometer

Download the App on the Apple Store by clicking this Button
“NOTE:
The App is just for iPhone with flashlight. It doe NOT work on iPad, iPod touch or any iOS device without flashlight.

Description:
Using this App, you can control the flashing on/off speed of your phone flashlight between 1Hz to 130Hz. In another word, this App makes your iPhone into a strobe light.

What’s the Application then?!
You can use this App to use your iPhone as a tachometer that measures the speed of any rotating object.

How to use it?
Suppose you have a fan and need to measure its speed (RPM). Turn on the fan in a DARK environment, launch the App on your iPhone (that has flashlight). Manually tune the speed using the main slider of the App to see the rotating object looks almost not moving. Then, start fine tuning using the three buttons in the App to get the exact speed. At this point the rotating object looks like stationary! But, it is moving! So, never touch the moving/rotating object during your test!

Features:
– Slider to adjust strobe light speed between 1-130Hz (60-7800RPM)
– x2 and ÷2 buttons for quick adjustment of flashing speed
– 3 Buttons for fine tuning of the speed up to 2 decimal: 0X.00, 00.X0, 00.0X
– Textfield to manually enter the speed in RPM (tap on the speed label)
– Button for light and dark background option
– showing the speed in both Hz and RPM
– simple and easy to use!!”

3. Strobe tachometer (RPM meter)

Download the App on the Apple Store by clicking this Button
“STROBE TACHOMETER
When the flicker frequency of light coincides with the speed of any object, such as a fan, the rotating fan may appear to be stationary. Changing the frequency of the flicker of light may help detect the rotation speed.

You may easily use the flicker frequency control buttons to quickly assign the flicker frequency with an accuracy of 0.0001 Hz (0.01 RPM):

• Up to 1000 Hz (60 000 RPM) for a connected flashlight (see the video on YouTube: https://youtu.be/iq6Xiums05o).
• Up to 100 Hz (6000 RPM) for the iPhone flashlight (iOS 7 and 8).
• Up to 40 Hz (2500 RPM) for the iPhone flashlight (iOS 9+).

IF THE SPEED IS MORE THAN UPPER LIMIT, YOU MAY STILL DETERMINE THE SPEED BY FIRST MAKING MEASUREMENTS WITH A LOWER FLICKER FREQUENCY AND THEN MAKING A SIMPLE CALCULATION (AS EXPLAINED IN THE APPENDIX).

To change the frequency, you should simply press and hold the button. The flicker frequency can be displayed either in Hz or RPM.

The image you see will be sharper in lower external light.

After a long period of usage, in case of overheating, the iPhone flashlight turns off automatically.

LASER TACHOMETER
• Measurement range from 0.3 Hz (18 RPM) to 1000 Hz (60 000 RPM).
• Step 0.01-0.0001 Hz (1-0.01 RPM).
• Update time 1 sec.
• 5 mW laser power required.

MAGNETIC TACHOMETER
This tachometer operates by measuring the magnetic field from a spinning magnet. The magnetic field is measured by the iPhone’s magnetometer. The magnetic tachometer is best suited for measuring low rotation speeds (from 6 revolutions per minute). It can also be used for measuring medium rotation speeds (up to 2,700 RPM), but at such speeds there is a risk of spontaneous tearing away of the magnet and strong vibration due to center-of-gravity shift.

• Measurement range from 0.1 Hz (6 RPM) to 45 Hz (2,700 RPM).
• Step 0.2-2 %.
• Update time 2-5 sec.”

4. Video tachometer

Download the App on the Apple Store by clicking this Button
“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.

Videos can be captured using the iOS “Screen Recording” function.

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 1000 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.”