Pretty much all people are attached to their phones these days, but it turns out yours might give you a rash. NYC-based dermatologist Nava Greenfield says metals in your phone like nickel and cobalt can cause an allergic reaction. Also, if you have a rubber phone case it could cause skin irritation as well; and your phone could give you zits, as it blocks your pores when you hold it up to your face to make a call. In addition, there's a chance the light and infrared energy from your phone could cause hyperpigmentation, or dark spots, on your skin. (Women's Health) Pretty much all people are attached to their phones these days, but it turns out yours might give you a rash. NYC-based dermatologist Nava Greenfield says metals in your phone like nickel and cobalt can cause an allergic reaction. Also, if you have a rubber phone case it could cause skin irritation as well; and your phone could give you zits, as it blocks your pores when you hold it up to your face to make a call. In addition, there's a chance the light and infrared energy from your phone could cause hyperpigmentation, or dark spots, on your skin. (Women's Health)