Android Android is a kernel-based Linux operating system designed primarily for touch screen mobile devices such as smartphones or tablets, initially developed by Android, Google Inc. supported financially and later bought the company in 2005. IOS is a mobile operating system of Apple Inc. Originally developed for iPhone (iPhone OS), beingthen used in devices like the iPod Touch, iPad and Apple TV. Apple, Inc. does not allow the installation of third-party iOS hardware.

There are several ways to connect electronic devices to each other; cables, infrared, etc. Bluetooth technology is one of them and enabling wireless transmission of voice and/or data between devices by radio frequency.
It is a technology of radio waves at short range (2.4 GHz) whose objective is the communication between devices such as computers, smartphones, tablets, printers, headsets and other dispositives hand.
Bluetooth is called the communication protocol specifically designed for low-power devices. These devices can be classified according to their transmission power:
- Class 1: 100 mW, maximum range approximately 100 meters.
- Class 2: 2.5 mW, approximate maximum range between 5 and 10 meters.
- Class 3: 1 mW, maximum range approximately 1 meter.

We can also classify this technology by standard. All these versions have backward compatibility, ie, it allows the latest standard is compatible with all previous versions.

- Version 1.2: 1 Mbit/s
- Version 2.0 + EDR: 3 Mbit/s
- Version 3.0 + HS: 24 Mbit/s
- Version 4.0: 24 Mbit/s

When calculating the life of a battery it will be necessary to know the number of charge cycles that can be performed until the battery does not begin to lose its capacity.
Depending on the type of battery these charging cycles can vary, the most common being the mobile batteries, manufactured Li-Ion or Li-Po, which have a duration of between 300 and 500 charging cycles according to model and manufacturer.
Once thisE limit we will notice how the battery loses duration of operation, arriving to lose up to 25% of its capacity of load.
At this point it will be necessary to evaluate a battery change.
It should be noted that usage and charging habits can significantly affect battery life. For example, factors such as heat, charge the battery several times a day without it is almost exhausted, etc. Will be affectedits duration.
Therefore, to get the most out of the battery we must know when a full charge cycle is performed, and try to avoid misuse of charge, to increase its useful life.
A charging cycle is considered when the battery has been discharged or its 100% charge has been used.
The manufacturers advise that the charge is never made below the 58% battery, since the battery voltage would not fall so lowTo, so you could end up winning up to 4000 charge cycles.
Tips to increase the life of a battery.

• Avoid extreme heat or cold or very long applications of the device.
• Charge the battery as often as you can.
• Fully discharge the battery from time to time.
• Do not let the battery run out completely before charging.

Below is a table with theDifferent voltages (V), charge cycles (C) and battery percentage (B).

Depending on the need for installation and type of base, trolley or chair, we can find various types of fixation. Among the most common we find:

A - Through hole: It has a hole in which a screw or stem is inserted. It is a very simple installation system. Ideal for wheels that should not support a lot of load.
B - Threaded stem: It has a threaded stem or nut, it is fixed to the surface with a nut. It is usually the most used fastening system.
C - Angular plate: They are usually less used fastening systems, they have lateral plates to fix on the base.
D - Plate: It has a rectangular or square plate on its surface, it includes 4 or more fastening holes to the base, it is one of the most common.
E - Smooth stem: The stem without thread is inserted into the female of the base, we can find it in the typical office chairs with wheels, TV furniture etc ...

The DPI refers to the precision of the mouse cursor. It is a measure of mouse sensitivity, where a higher DPI value means that the cursor will move faster on the screen with small mouse movements.

A mouse with a high DPI can be beneficial for tasks that require precision, such as first-person shooters, graphic design, and video editing. With higher DPI, the cursor will move faster on the screen with small mouse movements, allowing more control and precision in cursor movements. However, it can also be more difficult to control if you are not used to working with such high sensitivity.

In addition, a mouse with a high DPI can also be useful for those who use high-resolution screens, as it allows you to move the cursor more accurately on a larger screen.