Streaks and smears on a monitor screen are simply inevitable, and the safest way to remove them is to use a cleaner especially made for computer monitors, says Falko Hansen of the German telecommunications advice portal teltarif.de.
"Other solvents may damage the monitor surface," he warns, which means regular home window cleaning fluids are taboo, since they could theoretically leave their own streaks on the monitor. Some monitors have protective layers on them that may chemically react with substances in a household cleaner.
One safe cleaning option is to use a moist cloth. This should be wrung out well beforehand to make sure water doesn't spill on the device. Water might get into the edge of the screen and evaporate, leaving behind crystallised mineral deposits.
If that all seems too complicated, consider buying special cleaning cloths, which work just like the cloth one might use to clean a pair of spectacles, just packed with a safe mix of cleaning substances.
There is no risk of liquid entering cracks. The only downside of the towels is that they dry out quickly.
To simply clear dust, consider microfiber cloths. Cotton and paper towels are also acceptable options.