Report : 5 tests every iPhone goes through

1. Sit test

The first is the Sit test, where Apple sees what kind of damage iPhones suffer when an owner accidentally sits on them. The company undertakes this test as a three-part process.

The test involves the owner with an iPhone in the back pocket sitting on a hard surface. In the second test, the owner sites on a softer surface, like a couch or cushion. The third, which has been described as the worst-case test by ReCode, involves the owner sitting down on a hard surface such the iPhone and the surface are at an angle.

2. Three-point bend test

In this test, weights are put on the iPhones in order to check if they will bend or not under considerable weight. During the tests, a 25-kg bar was used to apply pressure on the middle of the iPhone's back in order to see if it bends.

Though the iPhones that were used for this test did bend, they reverted to their original shape once the pressure was lifted. However, Riccio said that an iPhone, or any phone for that matter, will bend permanently if enough force is applied.

3. Pressure point test

In the pressure point test, the iPhones are held by the edges and "substantial" force is applied at the centre of the back (the demo showed a weight of 10kg) hundreds of times to see that the device can revert to its original state after being bent.

4. Torsion test

Another test is the torsion test where the iPhones are twisted and torqued from both ends at various angles for about 8,000 times. The degree to which these products are twisted was not confirmed by Apple.

5. User studies

In this test, Apple employees with the highest usage rates on their iPhones are handed new iPhones to see how the new models perform in day-to-day situations on durability and performance parameters. Apple then checks these units for any issues.