An e cigarette is a cigarette that effectively uses a steamer and an electronic cigarette to vaporise a nicotine laced liquid into your lungs. While the nasty carcinogenic stuff found in tobacco is largely eliminated this does not resolve the underlying issue in an active nicotine addiction. In many cases the smoker returns to smoking and often with a higher tolerance to nicotine than when they were smoking cigarettes.
It’s for this reason few health organisations recognise inhalers, vaporisers or cigarettes as viable options for the task of smoke cessation.