I prefer the tower of amon thrall. It's just a much longer game. however this is a fun addicting game. I'm not sure what you could add on to the concept in later levels but this game has a solid foundation which would be perfect for a full fledged android game. looks like it would work perfectly on touch screens.
exhilarating. plays like doom but more action packed. makes good use of the metroidvania style which has become popular over the years.