What information can you extract from Wifi networks without connecting? Android newbie here.

I am not talking about eavesdropping wifi traffic, but accessing publicly broadcast information.

When you open the list of available wifi networks, that means Android is constantly capturing some information from all of them. It could be simply the SSID and signal strength. But what other information is broadcast by access points that could be extracted by a smartphone app without actually connecting to the network? Any sample code as a starting point?

On a related note, is it possible to connect to two or more wifi networks at the same time, maybe in a way similar to load balancing?
The following information can be found when  the device is near a Wifi Access Point (AP) even though the device isn't connected:

Apart from ESSID and Signal strength, 


MAC (for associated access points)
Bit rate
Channel: the frequency channel
Encryption
RTS ("Request to Send") threshold (generally the lower the threshold, the more stable the Wi-Fi network)
Fragmentation threshold 


To manipulate the basic wireless parameters you can use the iwconfig command.


  iwconfig command  is dedicated to the Linux wireless interfaces. It
  is used to manipulate the basic wireless parameters such as ssid,
  mode, channel, bit rates, encryption key, power and much more. To
  display information about wlan0 wireless interface, enter:


iwconfig Interface-Name-Here, 


iwconfig wlan0

To determine an interface, run netcfg

Here is the sample code

$ iwconfig wlan0


and gives the output as:

wlan0     Qcom:802.11n  ESSID:off/any
          Mode:Managed  Channel:0  Access Point: Not-Associated
          Bit Rate:0 kb/s   Tx-Power=0 dBm
          RTS thr=2347 B   Fragment thr=8000 B
          Encryption key: Off