use alcohol. period.
1. Alcohol kills germs. If you want dead germs, use alcohol.
2. Alcohol evaporates quickly and leaves no residue behind like other cleaners and bleach will.
3. Other "solutions" contain water. Water = bad for electronics. You can clean a circuit board with alcohol but I wouldn't try that with water.
Turn off your device. Remove the battery. Wipe it off with alcohol wipes. Let it dry for a few minutes. Feel better.