Must read:How to increase your android internal storage
For Christ sake how have you used 5GB on a new phone. Still confused? Read along you will know where the 5GB is being used.
When manufacturer produces a phone there is need to install Os on it right? The Os is called the ROM which contains all the whole interface of the device starting from the boot system, recovery, preloader, cache, userdata, and many more. But do you know what? this ROM is installed on the same partition of the internal memory which takes up to 5GB from the total internal space. So if you have always thought of it where the used space came from! Then it is from the system ROM eating some little GB from your Partition.
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