WiFi Battery Charger Prank

Battery Down? Whoever regularly faces this problem, get in line for a wonderful solution theoretically presented in this application?
Are you always annoyed of the low battery status of your android device. Here is a concept which can become a reality. In this application we have presented the concept of charging an android device through the electromagnetic waves that are emitted by the WIFI modem. Forget all the problems of the battery draining and get your device charged through WIFI.
Here is how it should work:
WIFI access points cover from 150-250 meters.
For ensuring effective network coverage WIFI access points emit some extra power. The most common and worldwide used WiFi networks (the 802.11a,b,g,n) emit in a range between -70 dBm and -90 dBm with a power up to 10pW.
Now when the electromagnetic waves reaches the android device, the waves are converted into electric signals and used to charge the battery of the device.
Enjoy this fun app with your friends and let us know about your experience. Your motivation keeps us moving forward and lets us think about interesting new ideas.
NOTE: This app is a theoretical concept and will not charge your device. So unless there is a practical implementation of this concept, smart android devices will not get charged.