Mikhail, well done. I hope that my corrections are helpful to you.

Please remember that every new sentence (after a full stop) needs to begin with a capital letter. For example:

       - Hello, my name is Tom. Yesterday I went to the park. Today, I will eat a big lunch.

Good luck, Tom 

Mobile phones

Mobile phones are presently one of the most important things of the present. Practically all the people on the Earth have phones, including me. so and me too. My phone is always with me and if anybody will phone or chat to me I will certainly answer. to this person. All phones have advantages and disadvantages of course. The most important thing about a  in the telephone is that you don't need to write a letter to somebody who is away from you, you can just make a call to him. But what about disadvantages? Phones make people depend on of their gadgets, and many people thinks that mobile phones aren't good for your the health because they have has a sound radiation.

mobile phones

mobile phone is one of the most important things in the present. practically all people on the Earth have phones so and me too. (my phone is always with me) I always carry my phone and if anybody will phone or chat to me I will certainly answer this that person.all phones have advantages and disadvantages of course. the most important thing of the telephone is that you don't need to write a letter to somebody who is away from you, you can just make a call to him. but what about disadvantages, phones make people depend of their gadgets, and many people think that mobile phones aren't good for the health because they has a sound radiation.