What piece of Technology is the most valuation in your life?-Tip

Mobile phone is the most valuation in my life, I think. Thanks for Alexander Graham Bell who is invented first telephone. From home telephone to cellular phone or wireless phone or mobile phone was innovation of telephone. Why is it the most valuation? People in this century need mobile telephone. It is useful for business communication and relationship from people to people. It can find where is people. It has many accessories such as camera, TV, video, mp3 and internet. It is make small world. It is cheaper and faster than other communication. Mobile phone made my life convenient and comfortable.