The mobile phones that are manufactured undergo vigorous testing before they hit the stands. The mobile phones are subjected to various kinds of tests that simulate the real time stresses that a mobile phone may undergo. The first and most important of them is the trouser test, which is a simulated test of the way a mobile phone stays in a trouser pocket. The simulator tests the mobile at various positions like the real effect. Then the mobiles are subjected to a couple of endurance tests like the twist test, break point test and gym test. The last of all tests is the scratch test, wherein the mobile is put in a bowl of plastic balls.