Seems about right. I read an article awhile ago that f2p games have less than that who actually go on to pay(about 2% iirc).
Considering their mobiles efforts are pretty much promotional games for their hardware and ecosystem, rather than whalehunters, it makes sense. They could make a whalehunter though and fatten the game up by using radom/procedurally generated levels, that would torpedo the design of each level and compromise gameplay, but the mobile crowd and a lot of the gamers complaining would likely eat that up.
They can then ration out free lives, have pay for characters(they could endlessly pump them out really) and costumes. They'd probably need to rachet up the difficulty as well to make those free lives worth getting, or rather pay for.







