Does the phone make life more convenient?
Yes, I do think so. A phone allows people to contact each other even if they are in different places. We don’t need to waste time on sending mail or traveling directly. It makes our life more efficient.
What are the advantages of using the phone?
The advantages of using a phone are : it helps us save time, and makes our life more efficient. Besides this, thanks to the smartphone and the Internet, we live in a global village where we can connect (with) people from different countries.
You can also use the colon to make a list like :
The advantages are : .... , .... , and ....