A widely-cited analyst echoed previous rumors about the iPhone 5S while adding that there will be a 128GB option for the new phone and possibly a 64-bit processor.
In February, Apple began offering a 128GB option on the iPad 4 for the first time.
And gold will be a color option on the upcoming phone, Kuo said, echoing a previous report from Japanese site Macotakara.
The analyst also claimed Thursday that the iPhone 5S will include a new A7 system-on-a-chip (SoC) based on ARM's 64-bit ARMv8 architecture.
That would be significant as Apple's previous A series processors and popular ARM chips used in smartphones are 32-bit.
Generally, 64-bit chips can address more memory and, thus, can be better at running more demanding software. The A7 is expected to boost performance over the A6. (Kuo said it will be more "efficient.")
The rear camera on the 5S will keep the 8MP sensor but get a larger f/2.0 aperture (that would match the HTC One) with dual LED flash -- confirming rumors circulating last week. If accurate, that aperture would be significantly larger than the iPhone 5's, i.e., more light gets through, improving image quality and low-light performance.
Kuo also repeated another rumor going around last week about a sapphire home button with fingerprint sensor.
The 5S announcement is expected in mid-September.