Work tools that can be replaced by a smartphone

In this, we’ll take a look at on-screen rulers, tape measures, levels, and metal detectors for Android. Sensors and various smartphone elements allow you to create other tools – for example, a compass, speedometer, sound level meter. But because such devices are rarely used in everyday life, they are not included in the review.

The selection of applications in each category is based on their popularity in the Play Market. Testing carried out on an Honor 5A smartphone.

The idea behind this type of application is straightforward; it does not require any special sensors at all. A ruler is displayed on the screen, which needs to be calibrated for actual values, and it will be ready for use.



The application is developed by Xalpha Lab and does not support Russian. But it has over a million downloads in the Play Market, so the program can be considered one of the most famous lines for Android.

Also Read: Why Keenetic Hero 4G router is best?

After launching the application, two lines appear on the screen – on the left and the top. With their help, you can determine the size of a small object that fits on the net.

For the measurements to be correct, the RulerRuler must be calibrated (for example, after starting the program, it determined the screen length to be nine centimeters when it is more than eleven). For calibration, you can use a regular ruler or some object of known length. But if such a thing or RulerRuler was not at hand, then an ordinary credit card or coins, the sizes are known to the program, are suitable for calibration. Unfortunately, the program does not see the size of Russian coins, and only coins of the USA, European Union, Canada, Australia, Great Britain, or Sweden are suitable for calibration.

The user has access to both the metric system of measurement and imperial in inches. Supports night mode to save battery power.

The program can remember the measurement by writing it down in history. That is convenient when you measure several items at once. But during testing, the application did not save history for some reason.

The Ruler does not contain ads. However, the user can purchase a similar paid application in the Play Market to support the developer (which the program always reminds about when closing).

⇡#” Line: Smart Ruler “

The application is developed by Smart Tools, which has created a whole package of working tools for smartphones – compass, metal detector, sound level meter, and so on. The program is fully Russified. The free version of the application will show ads to the user. In the paid version, in addition to the on-screen RulerRuler, there is a protractor, a set of templates for determining the pitch and profile of the thread (thread gauge), level, and other tools.

After starting the application, the RulerRuler, like in RulerRuler, needs to be calibrated. But can only do this manually by measuring the screen’s length and entering the data in the calibration field.

Unlike RulerRuler, in the Ruler: Smart Ruler app, you can measure objects by placing them in the middle of the screen and indicating the beginning and end. However, you cannot measure the length and width of an item simultaneously in the free version of the application. It is not possible to save the measurement results here either. But the application allows you to measure an object longer than the screen – for this, and you can move the RulerRuler to the left and the item.

The units of measurement can be either inches or centimeters.

⇡#” Ruler.”

The application was released by the Russian developer NixGame, which offers users other similar working tools. You will have to put up with advertising in the free version, and saving the measurement results will not be available.

To calibrate, you must attach an absolute ruler to the screen and move the screen ruler so that the divisions coincide. To measure the length, you can use either side of the screen as a regular ruler, put an object on the screen, manually set the start and endpoints, and measure the object’s length and width at the same time.

As with other apps, you can measure items in centimeters and inches. The app supports night mode and screen rotation.


To create tools of this type, you usually need to have an augmented reality library from Google – ARCore. But some applications can determine the distance to an object using the laws of trigonometry, using the data on the angle of inclination of the smartphone, which they receive from the gyroscope.

AR Ruler App


AR Ruler application was developed by the Belarusian company Grymala. The program uses augmented reality (AR) technology to measure distances and sizes of objects.

The program can measure linear dimensions of objects (in metric system or inches).

Distance from the device camera to a point on a plane angles on 3D planes, area or perimeter of an object (both rectangular, polygonal, and round), the volume of three-dimensional objects, and path length smartphone, the height of objects (for example, a doorway or furniture). There is also a simple on-screen ruler in the application.

AR Ruler requires the ARCore library from Google, which can install smartphones with Android 7.0 and higher. To improve the accuracy of measurements, the developer advises taking three sizes or more and focus on the average value.



Google develops the application. Like the previous one, it allows you to measure the linear dimensions of objects, the distance from the camera to the item (like a tape measure), the height of things, and so on.

You can take a snapshot of the measurement and also copy the results to the clipboard.

⇡#” Rangefinder: Smart Measure “

The program was developed by Smart Tools and the already reviewed “Ruler: Smart Ruler” application. “Rangefinder: Smart Measure” can measure the distance to the object and its height. The principle of the program is based on trigonometry. The ARCore library is not required so that you can use this “roulette” on smartphones with Android 4.0 and higher.

To measure the distance to the object and its height, you must first, aiming the cross at the base of the item, press the button on the screen, and then do the same concerning the upper point. Then the program will calculate the distance to the object and its height. For the best measurement accuracy, you must hold the smartphone at the height of 30 cm less than your size.

The program provides for manual calibration: the user is required to measure the actual distance to the object and its height and indicate how many percent the values ​​measured by the program differ from the actual ones. When tested, the program showed pretty good results, differing from the real ones by no more than 5%. From the reviews on Google Play, one can judge that the measurements are so not accurate in all cases. Perhaps it depends on the smartphone model.

The paid version of the program does not have advertising and supports measuring the width and area of ​​an object, portrait mode, camera scaling, and so on.


This type of application uses the device’s gyroscope and accelerometer to determine the angle of deflection on either side of the smartphone or its back.

⇡#” Laser level – leveling tool.”


The “Laser Level: Leveling Tool” application was developed by EXA Tools, which has developed several other similar applications. The program includes three instruments – laser level, bubble level, and inclinometer. The application is fully Russified.

For more accurate measurements, the application may need to be calibrated. To do this, you need to find a perfectly horizontal surface and calibrate the application data against it. However, it is not easy to figure out how to do this – the program does not contain relevant tips, which users also complain about in the Play Market comments.

When tested, the application showed pretty good results. Of course, building a house using only this level is not worth it. Still, in some everyday matters, such as installing a cauldron on a homemade hearth in the forest or a washing machine in an apartment, a smartphone can help a lot. Also, the application’s capabilities depend on the operation of the smartphone’s sensors – on the Play Market, reviews about the program are mostly diametrically opposite.

The program’s paid version differs only in the absence of advertising; you can switch to it from the free version right in the application.

⇡#” Building level.”

“Building level” – the development of the already mentioned NixGame. The application contains two tools – a level and a ruler. However, the line here – just additional functionality, the same developer’s appropriate application has used Ishimi capabilities. The program is fully Russified (and supports 14 more languages).


As in the previous application, you can calibrate the level by placing the smartphone on a perfectly horizontal surface. However, if the back cover is slightly convex, then accurate calibration may not work since the device will not be stable on the body (this remark is also true for all other programs of this type).

 Can use the level in two ways. The first one involves aligning the object by placing the smartphone with the back cover on its surface. It is necessary to ensure that the bubble in the center of the screen fits into the bounding circle. The second method involves aligning to one of the sides of the smartphone. In this case, you need to try so that the lines showing the angle of deviation from the calibrated horizontal line coincide with it.

When the ideal horizontal is reached, the application can inform about this with a sound signal.

In the paid version of this application, there is no advertising, and there is the functionality of the so-called plumb line (in fact, it coincides with the “laser level” in the previous application).

⇡#” Bubble level.”


Simple applications have no additional features. On the main screen, three bubble level icons allow you to align the surface on the smartphone’s side, on the bottom, or the back cover (in several places at once).

In addition to the level, the program has only one option – its calibration. Moreover, the developer claims that it will just need it when the smartphone manufacturer has not adequately calibrated the device. This remark seems to be true for other applications only because the developers do not declare it. When testing all applications of this type without calibration, we found no difference in measurement accuracy. The paid version differs from the free one only in the absence of ads.

⇡#” Level.”


In terms of functionality, the “Level” application is similar to the “Bubble Level,” with the slight difference that it is automatically able to determine on which side of the smartphone the surface is aligned (side, top, bottom, or back cover) and show the corresponding level on the screen. The desired type of story can be fixed so that the interface does not change when the smartphone moves.

The program can inform about reaching the horizontal with a sound signal. The level can be calibrated if necessary.

The paid version differs from the free one in the absence of ads.

⇡#Metal detectors

This type of application depends on the presence of a magnetic sensor in the smartphone and its sensitivity.

⇡#” Metal detector ” from Smart Tools

This application was developed by the already mentioned company Smart Tools co. The developers suggest pointing the smartphone up and drawing an eight or rotating the smartphone in three planes to calibrate the application.

During testing, the device efficiently reacted to a paper clip lying on the floor (although you can see it anyway) but practically did not feel the staple clip and the needle. Nor did he determine the location of the electrical wires in the wall. By the way, the repeated calibration did not affect the device’s ability to search for metal.

So on the Honor 5A, the app is essentially useless.

⇡#” Metal detector ” from Netigen


The application is developed by the Polish company Netigen and does not support Russian. The company, like other similar developers, offers a range of working tools for the smartphone.

During testing, the application showed the same results as other metal detectors: detected large metal objects brought to the sensor, but small items or wires in the wall were not.

Users of the program will have to put up with advertising, which is much more than in the “Metal detector” from Smart Tools co. There is no paid version.

⇡#” Metal detector-magnetometer “


Application the game developer Appeal. The operation principle is approximately the same as that of previous programs, only due to its specificity. The developer has built some game functions into the application – for example, and it offers to select the items that the user will look for (treasure, essential things.). In the description of the program, the manufacturer recommends using the application for pranking friends.

When tested, the application showed worse results than previous programs – for example, it practically did not respond to a metal clip.

⇡#” Metal detector ” from RZTech

This program differs from previous applications in the absence of metal detector calibration. There are a lot of ads in the application; there is no paid version. The Russian language is preinstalled.


Even a simple smartphone can be a good substitute for tools such as a ruler or a level, showing reasonably accurate measurements. To fully use your smartphone as a tape measure, it is best to have a device with Android 7.0 or higher, but the accuracy will still not be up to a centimeter. As metal detectors, smartphones do not seem to be very good, but perhaps the reason is precisely the weak magnetic sensor on the device under test.

Write A Comment