How does an anti-mosquito sound work

Inaudible to humans, the cell phone is supposed to emit high-frequency tones and thereby chase away stinging mosquitos. Several apps promise peace and quiet from mosquitoes and sometimes other insects. Chip-Online tested one of the applications and came to the conclusion that the app "filled the mobile phone with advertising without consent, and in several places at the same time. We therefore expressly warn against the download."

Use: Repelling mosquitoes is of great value in malaria areas. In this country mosquitoes pose no threat, but almost everyone would like to keep the pests at bay. Many years ago, inventors came up with the idea of ​​deterring mosquitoes with high-frequency ultrasound. Special devices have been developed - and have long been scientifically investigated. The Cochrane Collaboration, known for its strict criteria, denied the devices any use. The theory behind the technology is also not plausible, the researchers wrote: Female mosquitoes hear very poorly. Whether the sounds come from a special device or the smartphone - it is very likely that they will not reach the insects at all. Stiftung Warentest puts it this way: "Whoever kills mosquitoes with the iPhone is more successful."

Alternatives: Certain mosquito repellants, covering clothing, mosquito gauze on windows and doors and mosquito nets around the sleeping area are somewhat more effective.