Capacitive touch screens work on the basic principle of activation of sensors when very diminutive electro-chemical charges dissipate on its surface. Thus, when we touch our fingers onto the sureface these charges are activated.
Snapshot of the 20 bucks stylus:(1)
1) A gel pen with the refill removed;
2) A board pin with a domed metallic surface;
3) Copper wire; and
4) Aluminium foil.
Time for the project-
Let's get started!
The improvised stylus(2):
1) Strip the ends of the copper wire;
2) Coil one end around the sharp point of the thumb pin;
3) Thumb the pin into the back of the pen;
4) Now, wrap a bit of the aluminium foil around the pen so as to act as a grip as well as a conductor; and
5) Stick the copper wire to the foil with the help of sticky tape.
Your stylus is ready to do wonders on your touch screen device!
P.S.: It is also scratch-resistant!