The client is waiting a full second to give all DHCP servers the ability to answer the request for an IP address offer.
Then the client will choose the best offer and will tell that DHCP server it took the offer.
I think after that the DHCP server is letting all other DHCP servers know the current status of available IP addresses. Maybe that will also take some time (with a lot of waiting, time-outs and stuff).
But then the question remains why should it take more than 2 seconds?
I think it's apples and oranges to some degree - a macbook pro with a venerable operating system versus a tablet with one that's still heavily in development.
Better to compare galaxy vs ipad tablets, or osx vs other unix vs windows
