A phone strap, cell phone strap, or mobile phone strap, was originally a string or loop to help the user hold their cell phone, which was invented and became popular in Japan where they are known as "keitai straps" (携帯ストラップ) in Japanese. Phone straps have now become a cultural phenomenon beyond their basic utilities, and they may be decorated or themed with famous characters such as animation heroes or Hello Kitty. Phone straps may also have additions to add additional functions such as detecting ghosts, carrying medicine pills or mobile gardening.