Why my iOS didn’t update

Henrick01 wrote:

Because I want to update my iPhone

Assuming you have a compatible device, see: Update your iPhone, iPad, or iPod touch - Apple Support

And: If your iPhone, iPad, or iPod touch won't update - Apple Support If the above Apple articles do not help, please post back with relevant information. 

Henrick01 wrote:

so I can download the apps I want

Which device?

What is the existing version of iOS?

Henrick01 wrote:

To be able to update

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