Always carry a handful of fine grade steel ( Grade 000 )wool in your pouch, its great for removing specks of paint, stubborn fly pooh, vanish etc.
Its great for giving new cleans that final sparkle to the glass. Don't worry it doesn't scratch the glass.
One word of warning though... don't put your mobile phone in the same pouch, it will kill it stone dead.
I know this from past experience.
Denzle