Didn't have any trouble installing Crystal Maidens (including updating this morning) or armor blitz on my phone, but this one, I download it, it goes to "install blocked", I click settings, check unknown sources, hit ok, it asks if I want to install, I hit install, it goes to installing...
Then pops to "App not installed".

(I had installed the google play version earlier, but quickly uninstalled it because, why bother?)