If you want to get an idea of how well a sapphire glass display protects a phone, check out this video from Kyocera showing off its Sapphire Shield smartphone cover in action.
The video shows the sapphire cover faring MUCH better than a standard impact-resistant cover in scratch and drop tests. After various levels of abuse, the impact-resistant cover is ruined, while the sapphire cover looks like new.
Kyocera’s Brigadier smartphone is one of the few smartphones available with a sapphire display, Apple’s upcoming iPhone 6 is expected to sport a sapphire display, although some reports say production issues may not allow the use of sapphire for this generation’s handset.