Method 1: The Classy way
1. Go to Settings
2. Select Wifi Settings (just tap on "wifi" of 'wifi on/off button' )
3. Select Advanced (In the right bottom you will see menu or just three dots,expand that)
4. At the bottom you have MAC and IP addresses.
Method 2: The Cool way
1. Open dial pad and type *#*#4636#*#*
2. Select Wi-Fi infromation
3. Select Wi-Fi status
4. You should be able to see IPaddr and MAC addr, in case if they are blank just tap 'Refresh status'.
