This situation revolves around the dangers of absorbing radio-frequency energy into the brain. Although the constitutionality and impact of this can be debated, many countries have imposed a legal limit on radio-frequency power output. The iPhone, in Apple’s example, uses the proximity sensor to identify when you’re holding your phone against your head and, as a result, reduces the RF output. However, regulators in France have gone one step further by enacting legislation that states that users should be deliberately encouraged to avoid holding their phones to the side of their heads. Instead, the country advises using headphones when on the phone. The purpose of French legislation is to protect children under the age of 14 from RF.