I believe mobile devices use active scanning instead of passive because it reduces battery usage. It reduces battery usage because it means the wifi radio does not need to be listening constantly for beacon frames.
Célestin Matte. Wi-Fi tracking : Fingerprinting attacks and counter-measures. Networking and Internet Architecture [cs.NI]. Université de Lyon, 2017. English. NNT : 2017LYSEI114. tel-01921596f
Célestin Matte. Wi-Fi tracking : Fingerprinting attacks and counter-measures. Networking and Internet Architecture [cs.NI]. Université de Lyon, 2017. English. NNT : 2017LYSEI114. tel-01921596f
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