Shimabuku. Mobile Phone and Stone Tool, 2014. Mobile Phone and Stone Tool: A mobile phone is one of the newest devices of humankind, and a stone tool is the oldest. Actually, they are similar in some aspects. Firstly, the size is similar. When held in a person’s hand, some of them feel very much alike. Stone tools also have “memory” just like mobile phones. You could imagine “calling” or “taking a photo” with a stone tool.