Android: Get the IP Address of the current device. In the latest versions of Android on the trunk this built into the platform so you will probably be able to just call an intent.

Android: get IP Address

WifiManager wifiManager = (WifiManager) getSystemService(WIFI_SERVICE);  
WifiInfo wifiInfo = wifiManager.getConnectionInfo();  
int ipAddress = wifiInfo.getIpAddress();  
String ip = intToIp(ipAddress);  
  
public String intToIp(int i) {  
  
   return ((i >> 24 ) & 0xFF ) + "." +  
               ((i >> 16 ) & 0xFF) + "." +  
               ((i >> 8 ) & 0xFF) + "." +  
               ( i & 0xFF) ;  
}