Following yesterday's rumor of an August 2013 release for the iPhone 5S, iMore reports that another source has confirmed the information. That's now two reports saying that we should expect the iPhone in August. All of this could turn out false, but two reports confirming the same month seems pretty legitimate.
Aside from launch date rumors, the iPhone 5S' general design is also touched upon. It's reported that the 5S will have the same basic design of the current iPhone 5, but feature a spec bump comparable to the bump seen between the iPhone 4 and 4S. It's specifically mentioned that the iPhone 5S will be getting a better camera, and hopefully one that doesn't suffer from purple tint.
Interestingly enough, iMore is reporting that Apple may be revealing its next iPad in April. We've already heard that the next iPad would be a marked improvement over last year's surprising, but underwhelming, fourth generation iPad.
It's also rumored that the company will announce a new iPad Mini next month as well, but it's unknown if it will feature a retina display.
I don't know if we should expect a new iPad this early in the year, but Apple has generally announced at least one major product during the first few months of the past few years. Last year's announcement was for the expansion of iBooks into educational materials, and a similar announcement, alongside new iPads to compliment the feature, would make sense for this year.