Why the new iPhone SE with 16 GB of memory has only 11 GB available?
You may have noticed that the amount of built-in memory, specified by the iPhone manufacturer, doesn’t correspond to the actual available amount. Thus, at the stated capacity of 16 GB, in fact, the latest iPhone SE has only about 11 GB of storage space and there is a simple explanation for this phenomenon.
First of all, we should refer to the notes on Apple’s official website, which state that under 1 GB Cupertino implies 1 billion bytes. That is, 16 GB contains 16 billion bytes. It is known that 1 Kb is 1024 bytes, respectively 16 “apple’s” GB contain 15,625,000 Kb.1 Mb equals 1025 Kb, so, if we divide 15,625,000 by 1024 we will get 15,259 Mb. 1 GB is 1024 Mb, so if we divide 15,259 by 1024 we get 14.9 Gb.
By other words from indicated on the box 16 GB the user gets only 14.9 GB. However, if you look at the information displayed in, for example, settings of iPhone 6 with iOS 9.0.2 (Settings ->General->About), you will see not 14.9 GB, but 11.9 GB. So, how did we lost another 3 GB? Another example, iPhone 6S 128 GB from which only 114 available for user (Minus 14 GB!!!). Returning to the Apple notes on the official website, they stating that after formatting, the actual capacity of the gadget becomes less than stated.
In short, this means that during the flash of operating system, memory is divided into two categories: the root system and the storage for user’s information and content. The first is designed for the mobile platform files, the second – for files loaded or created by user. So in the settings presented to the user, you will see only the second category, without any mentions about the allocated space for the operating system.
However, at this stage there might be a misunderstanding. The fact that different iPhone with different versions of the operating system has significantly different capacitance of the root partition. This is mainly due to two things: every new firmware version is usually larger than the previous one, therefore on new models the same version of firmware allocates more space than on the old. For example, in 2009, the iPhone 3Gs 16 GB had more than 14 GB of storage space available for user (firmware was only 300 Mb), while in 2015 iPhone 6s Plus 16 Gb – about 11 Gb (firmware size 2.4 Gb).