The little-known rule about your mobile phone at airports: they can confiscate it before you board.

Before boarding a plane, we must go through security where our belongings are checked, with special attention paid to our electronic devices such as phones, tablets, laptops, and the like. But there's a detail that not many people know about something we must do before going through security.

The goal is to ensure our devices have enough battery power to turn on. Airport security personnel are authorized to ask you to turn on your devices and confiscate them if you cannot, as the Daily Mail explains.

The reason is that authorities may consider a non-functioning device a security risk. If your mobile phone won't turn on, officers may suspect it's a counterfeit device or that it has been modified to conceal explosives or other hazardous materials.

These measures are especially taken into account in countries like the United States, the United Kingdom, or Israel , which are often targeted by terrorists.

Most airlines enforce these rules, including low-cost carriers such as Ryanair and EasyJet , and it is recommended that you keep your phone switched on until boarding, as further checks may be carried out until the last minute.

For example, British Airways states in its rules: "Airport security personnel may ask you to switch on electronic or battery-operated devices, such as phones, tablets, e-readers, and laptops, to demonstrate that they work."

"If you cannot do this, you will not be able to take your device with you . Make sure all items in your hand luggage are fully charged and turned on before you arrive at the airport," it continues.

"If your device is not charged, please place it in your checked luggage. If you plan to charge your devices, be sure not to drain the battery during the first part of your journey, as charging points at airports can be very limited and you may need an adapter," it concludes.