Apple has announced an event to be held September 10th. They are likely to reveal the new iPhone 6 and possibly other Mac products. Rumor is there will be 2 different iPhone 6 sizes, both being larger than the previous iPhone 5/iPhone 5S. Although I question the motive behind the two different sizes; it seems most other smartphone companies have at least 1 larger size available for consumers such as the Galaxy/Note.
The new iPhone screen is said to be made of sapphire – the same material the 5S uses for its new home button. The leaked screens have withstood intense flexibility tests and minor scratch tests. That being said, it can be concluded that it is not pure sapphire but a glass/sapphire composite, unlike the 5S home button which is pure sapphire.
Here is a short video of a scratch test conducted on a rumored iPhone 6 screen.
Also the new iPhone is rumored to only output a 960p resolution. Although Apple is not up to a 1080p display yet like its main competitor the Samsung Galaxy, the pixel density is still a very high 356ppi.
Final thoughts: With a new screen technology, iPhone 6 should have a very durable, drop resistant screen on the market. That being said, it may be much more expensive the conduct replacements on the new iDevice.