The problem is you need to be a programmer. And to allow a smart phone to turn on WiFi how would it do that since there is no WiFi to talk to the router when WiFi is off.
How about ones that do this on a schedule?
http://kb.netgear.com/app/answers/detail/a_id/24102/~/how-do-i-set-up-the-wireless-schedule-on-my-nighthawk-router%3F
Does anyone know of a wireless router that can be configured to automatically shut down wi-fi when it is not in use and then allow a smart phone app to turn on wi-fi only when it is needed?

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