Comparison Beurer PM 90 vs Beurer PM 25

The presence of backlight in the design of the display, which is equipped with the device.

Its own backlight allows you to see the image on the screen regardless of the ambient light — in other words, such a screen can be used even in complete darkness. Most often, it turns on for a short time, by pressing a special button — this allows you to minimize additional battery consumption. The exception is displays built on the basis of OLED matrices — in them each pixel is a separate luminous element, the image glows constantly, and energy savings are ensured by high efficiency and some design and software tricks.

Sensors and measurement modules provided in the design of the gadget.

— GPS module. A GPS receiver helps pinpoint a device's current coordinates. Its applications range from calculating distances in sports gadgets to more advanced functions such as full-fledged navigation with optimal route determination, depending on the device's features.

— Altimeter. The altimeter, detecting device height, operates through various principles. In GPS-equipped models, it uses a geographic database to determine height based on coordinates. Those with a barometer calculate altitude from pressure differences, often referencing a starting point or a hypothetical sea level. While the GPS method is more precise in measuring ground surface height, it overlooks objects like stairs or towers. Barometer-based measurement is affected by weather changes but provides the actual height of the device.

— Thermometer. A sensor that detects the ambient temperature. This data can be useful both for assessing general comfort levels (personal impressions can be deceiving, especially if you will be outside for a long time), and for specific tasks — for example, improvised weather forecasts (in combination with barometer data and other observations).

— Barometer. A s...ensor measures atmospheric pressure, commonly used to forecast weather changes. Its applications extend beyond this, including the ability to gauge height differences even when a dedicated altimeter is not present. It's worth noting that this function is applicable only to gadgets capable of displaying atmospheric pressure data on the screen; altimeters with barometric sensors lacking this feature are not included in this category.

— Compass. A traditional compass is a device for determining the cardinal directions, one of the basic instruments for any navigation. In modern heart rate monitors and other sports gadgets, usually, a digital compass is used, which displays data directly on the display.

Personalized settings enable users to tailor the device to their individual characteristics. Modern fitness devices often incorporate the following customization options:

— Gender. Ability to set the gender of the user. With the same age, height and weight, the male and female bodies still differ in metabolic characteristics, optimal heart rate values and some other significant parameters.

— Age. Ability to set the user's age. This indicator primarily affects the general condition of the body and its ability to endure high loads (although these points also depend on other factors, ranging from physique to physical fitness, previous diseases, etc.).

— Weight. The option to input user weight is used in calculating optimal heart rate, energy expenditure, and fat burned (refer to "Possible measurements"). When combined with height, it provides insights into physique specifics and the need for weight management.

— Height. Ability to set the user's height. This indicator is practically not used on its own — it is usually used in combination with weight (see above) when determining physique. In addition, some pedometers (see “Type”) can calculate stride length from height data (although this setting is more common, see below).

— Step length. Ability to manually set the user's average step length. The main scope of this data is the calculation of the distance traveled in pedometers (see "Possible measurements")....

— Individual training area. Users can manually define an individual training zone, specifying the desirable heart rate range during exercise, with a warning signal for exceeding it. While many fitness gadgets can automatically calculate an optimal range based on workout goals and individual settings, certain situations, such as recovery after illness or exceptional physical fitness, may require specific considerations. Some devices with a heart rate monitor function enable users to manually set a personalized training zone, factoring in all relevant parameters.

The degree of water protection provided for in the design of the device.

The specified underwater depth for device functionality is often given, but it's important to note that these values are somewhat arbitrary and don't accurately reflect real-world water resistance. The assessments only consider static pressure, neglecting dynamic pressure created by movement, including immersion.

Effectively, genuine water resistance can only be claimed at a minimum of 30m. Even then, such capabilities only withstand minor exposure like rain. Brief water exposure, like swimming, might be permitted at 50m (not universally). For depths of 2 — 3m, 100m is necessary, and serious diving requires a minimum of 200m (or 300m for depths exceeding 20m).

The device has its own built-in memory.

Almost every sophisticated electronic device has a certain amount of memory, but here we specifically refer to permanent memory. This type of memory is ideal for long-term data storage, ensuring information is retained even during power outages. Its presence enables the device to operate autonomously, storing training logs, individual settings, and other essential data without the need for communication with other devices.