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> Android WiFi crackers?
> I didn't see any root tools since Jelly Bean
As Android can install Termux, you can also setup a full Arch or Kali distribution there :) If you want to go full root + kali, TWRP is pretty straight forward for most devices these days.
With the above two techniques alone, I have a success rate of around 80%. If that doesn't work out, just crack the next neighbors' WiFi. Additionally, there's the WPS exploit, most people have WPS activated as they have no clue about how to configure their WiFi router, so that's also nice and works most of the time :D
edit: The krackattacks were the actual reason for the WPA3 spec btw. So it is known to work, and cannot be fixed by concept.
Android app for vulnerability testing is on GitHub: http://bit.ly/1RaqyuX
also available on Google Play: https://play.google.com/store/apps/details?id=net.yolosec.routerkeygen2