You forget a few things. On Android can't the app just run forever and decide on its own how often to poll the servers? This is a different thing. The OS decides when to schedule things if the app supports it.
Also battery life has improved a great deal since the first Android or iPhone device came out. What may have been true years ago isn't necessarily an issue anymore.
Also battery life has improved a great deal since the first Android or iPhone device came out. What may have been true years ago isn't necessarily an issue anymore.