The iPhone 13 will reportedly have a better battery life than its predecessors.
The highly anticipated device - and other handsets in its iPhone family - are expected to have larger batteries than the iPhone 12 series.
In an investor note, analyst Ming-Chi Kuo said: "The new 2H21 iPhone models feature a larger battery capacity than the iPhone 12 series, thanks to the space-saving design of many components.
"Hence, the new 2H21 iPhone models are also slightly heavier than the iPhone 12.
"The space-saving design includes integrating the SIM card slot with the mainboard, reducing the front optical modules' thickness, etc."
Although everyone is expecting the iPhone 13 - which is yet to be announced - there is also the possibility of Apple dropping a iPhone 12S range.