2013 iPhone event on Sept 10th

Apple is expected to unveil its next iPhone at a special event on Sept. 10... The launch comes at an important time for Apple, which continues to make a lot of money from the iPhone but has seen its global market share dip amid a growing wave of lower-cost Android devices, as well as an intense battle with archrival Samsung.
— Ina Fried, AllThingsD
Rumored iPhone 5S - Source: macrumors.com

Rumored iPhone 5S - Source: macrumors.com

Rumored iPhone 5C - Source: Gizmodo.com

Rumored iPhone 5C - Source: Gizmodo.com

 With the man with 100% success rate in predicting Apple's events and new products in the past, Jim Dalrymple confirming the Sept 10th, 2013 iPhone launch event, the next gen iPhone and a possible low cost iPhone along with it are positively confirmed. If the rumor mills are true, the iPhone 5S will feature a dual flash LED camera to enable better low light and indoor photos and also a fingerprint scanner (surprisingly but understandably convex and not the present concave shape). Except for these two enhancements not much has been uncovered about the iPhone 5S. Oh by the way there is also a rumor of a gold colored iPhone 5S, wait what?

Either way this will be the first time that Apple is releasing (at least) more than one new iPhone model at the same time

Coming to the low cost iPhone 5C, the rumors are that it will be 'cheaper' than iPhone 5S and will be available in a variety of colors. There is not much of a confirmation on how cheap the iPhone 5C will be or what compromises it will bare to make it cheaper other than the plastic body. Either way this will be the first time that Apple is releasing (at least) more than one new iPhone model at the same time, which might be an indication that iPhone will go the iPod way that once there is enough room to expand the market, Apple will widen the model base for the iPhone as well.

iOS 7 - Source: Apple.com

iOS 7 - Source: Apple.com

Along with the iPhone, iOS 7  should be announced and so far there haven't been rumors of any other products being announced on the Sept 10th event, though there are other almost certain product releases (like the iPad 5) and launches expected this fall.

iPad 5 concept - Source: iMore.com

iPad 5 concept - Source: iMore.com