For me, it is my mobile phone. It is a very great invention of our times, I would say, it is the only gadget which is and which has all-in-one in it. Yes. You can do a lot of things with your mobile phone. Some of the many things that you can do with your mobile, following are a few. 1. You can talk to someone and receive calls as well. 2.You can use it at anywhere you like and at any time of the day or night. 3. You can share information and photos through WhatsApp. 4. You can surf the internet. 5. You can see the movies you like. 6. You can use it as a camera. 7. You can download the useful apps you like enjoy the same. 8. You can use the inbuilt features like the ,calculator', 'torch' etc. In fact, the utilities offered by a mobile phone are manifold.