There is a program out called Bcmon that will allow monitor mode, wash, and a terminal window on a android device, how cool is it to be able to do wireless penetration testing from your Smartphone.
The way it works is most smart phones actually contain wireless chipsets that can be put into monitor mode and do everything a capable USB adapter can do. The problem has been the drivers, manufactures have never coded the drivers to enable this. Bcmon has re-coded the drivers to take advantage of the full potential the built in wireless has.
Bcmon isn’t plug and play there is some hurdles but depending on your ability this may not be that bad. First the phone will have to be rooted then cyanogenmod 9 or higher installed. After that Bcmon.APK copied to the phone and installed.
Also Bcmon hasn’t been tested on many devices. In the video I used a Samsung galaxy S2 which is listed as being compatible with Bcmon. Here is the Bcmon page, https://code.google.com/archive/p/bcmon/