Electroneum is a "mobile centric" crypto. Their app which is available on android doesn't actually do any mining in the traditional sense. In their ICO they delegated a certain amount of the initial coins to the mobile mining platform. The app runs a custom algorithm that estimates the hashing power of the device and uses that to collect ETN. at a rate of 110 H/s I get about 10 ETN per day. Current market value is $0.02 USD. so about 20 cents a day from a spare device isn't bad.

On the other side of the spectrum, if mining with a decent Core i5 or i7 the traditional way you can net about 3 ETN per day. That's why I say the crypto is entirely mobile centric.