The iPhone 7 Plus is rumored to be powered with powerful 3GB
of RAM and will have a dual lens camera on the back.
The iPhone 7 Plus is rumored to be powered with powerful 3GB of RAM and will have a dual lens camera on the back. 
According to KGI Securities analyst Ming-Chi Kuo, only the “Plus”
model will have more RAM than the regular model. That means larger-screened 5.5
inch iPhone 7 Plus will get 3 GB of RAM where as 4.7 inch iPhone 7 might have
2GB of RAM just like in iPhone 6S. 
Also previous rumor suggested that there will be three
different models of iPhone 7 i.e. 4.7 inch iPhone, 5.5 inch iPhone 7 Plus and
iPhone 7 Pro but the analyst claims that there will be only two models which
will include the regular 4.7 inch iPhone 7 and iPhone 7 Plus or iPhone 7 Pro.
Also the “Plus” model is rumored to be integrated with dual
lens camera system. The dual lens camera on the back is believed to shoot
stunning photos under any circumstances. According to the analyst, the reason
behind adding more RAM to the iPhone 7 Plus model is because of dual lens
camera as it helps in increased image processing.
The Dual Lens Camera System and 3GB of RAM will only be
available on high end model, that is iPhone 7 Plus. The 4.7 inch regular model
might have only one camera on the back and powered with 2GB of RAM.
iPhone 7 and iPhone 7 Plus is going to be unveiled on
September at WWDC event held by Apple. It is predicted to ship 20-30 million
units of iPhone in 2016 fiscal year.
Analyst also predicts that the new
iPhone shipments will be around 20-30 million units
in fiscal 2016.
Source: macrumors