I've decided to give this mobile miner a go but don't see why Electroneum have released it.
According to the info page on the miner it says..

"Mobile phones are not built to withstand or cope with the complex calculations required to perform actual crypto mining..."

So this means there will never be a 'real' mobile miner for Electroneum, which brings me back to my original question, why did Electronium produce what is, in effect, just an airdrop service.