Among everyone I mean grandparents, great grandparents, truck driver, waitress, inn keeper and all other laypeople included. Here goes: Viber: Cell phones should have the free tool installed. Then you can use the cell phone number on any digital device such as laptop, iPAD, TAB and others, provided Viber is also installed on these devices. It is meant for making free phone calls where there is also the option of video chatting.
Gmail: You should access this email client via internet on your cell phone and other digital devices. This is a free tool as well. You should sign up for this service and start sending out formal or cordial emails as you wish. Along with Viber, which is actually used for making phone calls, you can use Gmail for sending out emails to people with whom you think you can better communicate by using this tool.