Alien dalvik is only available on officially supported device (Jolla 1, Jolla C, Jolla Tablet, Sony Xperia X, Sony Xperia XA2 etc) While it is possible to run Sailfish on Nokia N9 it is very buggy and not stable enough to be used as daily driver so getting a working anbox or alien dalvik there wouldn't be much use. On other devices (including Nexus 5) there is no official (legal) way to run alien dalvik. Perhaps you can get anbox working there but from my understanding it is not ready yet so if you need android support I would suggest buying a Sony Xperia XA2.