Android PCAP implements the Linux kernel RTL8187 driver in userspace using the Android USB host API. This means it doesn't require root privileges (a highly dangerous requirement), and will run on stock phone firmware.

It is not possible to capture from the internal Wi-Fi interface on Android without running a custom firmware and gaining root access. Android PCAP was designed to get around those restrictions and provide a secure, standard method.

To go with PCAP capture, you can immediately view your PCAP files using the CloudShark service. To make this even easier on Android, check out CloudShark Uploader, which lets you send directly to CloudShark or a private CloudShark appliance!

Android PCAP should work so long as:

1. Your device runs Android 4.0 or higher (or, in theory, the few devices which run Android 3.2). Earlier versions of Android do not have a USB Host API
2. You have a RTL8187 based USB Wi-Fi NIC. A good example of this is the Alfa One 802.11b/g wireless card. In the future, additional cards will be added.
3. You have an OTG Adapter Cable. This cable enables USB host mode on the device. Devices which have full-sized USB host ports should work without an OTG cable.
4. Your device supports USB Host Mode properly. Some devices do not - see the compatibility section for more information.

The following is a non-canonical list of devices and support, if you find a device not listed that it works on (or doesn't work on) please let us know at android-pcap @ kismetwireless.net

Any wireless device based on the RTL 8187 chipset should work. This chipset can be found in many different wireless devices, but is easily found in the Alfa One NIC (the 802.11b/g version, not the 802.11a/b/g/n). This card has the advantage of being easy to get (Amazon, other online retailers), it's reasonably powerful and sensitive, and if you already use Kismet you probably already have one.

There are likely many (hundreds) of other wireless NICs which use the 8187 chipset. Specifically, any device with the USB vendor/device id of 0x0bda,0x8187 should work. You can find the device ID on Linux with the "lsusb" command, and on Windows in the Device Manager.

Android PCAP generates stock PCAP files of 802.11 packets with PPI headers. These can be processed by any of the packet handling tools, such as WireShark, Eye P.A., and Kismet. Combined with CloudShark for Android, PCAP files can be uploaded directly to the CloudShark site for decoding in your browser.

Driving a USB attached NIC will definitely negatively impact the battery life of your device.

Splicing in additional power (such as using a hard drive 'y' cable or battery powered USB hub) is highly recommended for long-term uses.

We are developing a battery-powered hub solution, with power feed options to support "weird" devices like Motorola phones. Stay tuned.

Capturing from the internal Wi-Fi on Android is not typically possible.

There are projects which are trying to hack in support for this, and when it becomes more stable, Android PCAP will attempt to support it, but currently these hacks require custom ROMs, specific phones, and root access.

Android PCAP was specifically designed to not require special hardware (except when phone manufacturers make weird decisions which cripple USB host), or excessive privileges (USB and external storage access).

Source for Android PCAP is available as a Git repository:

git clone https://www.kismetwireless.net/git/android-pcap.git

Android PCAP does not collect personal information from your device.

Collected wireless data is stored locally on the drive and transmitted only to a location of the users choosing via the "Share capture..." option.