Smart Stay is a new feature introduced by Samsung and is first used on its new smartphones, like Galaxy S III. It is now available for some other ...Continue
To change the ringtone of your Samsung Galaxy S2 or other Samsung Galaxy devices do as follows:
1. Open "Setting" App
2. Go to "Sound"
3. Find "Device Ring tone" and Tap on it
4. Choose your favorite music or tone as the new Ringtone