There is already Miners Gate and Other mobile miners. Mining with phones has its ideals as the chipsets as far as power consumption vs hashing power is better/more efficient. That said for the average mobile user its not ideal to have you phones chip maxed out hashing as you will drain battery fast and possibly over heat the phone.
The idea behind ETN mobile miner is to just check out what you phone would hash at, and give you coins based on that. So people without much money to put into crypto, people in counties where exchanges are banned, and putting fiat into crypto is hard, this is a option for people now to get some coins running the app in the background, as well having a mobile wallet that you could trade the ETN for other crypto or other crypto for ETN.
Not to mention ETN will be launching XBOX one and playstation miners. So all the parents who think crypto is ponzi ect their kids can now mine despite what their parents believe.
The marketing was done very well.