It is certainly not uncommon for your iPhone, whether it be 16gb or 256gb, to run out of available storage space. This can be frustrating, as it will likely prevent you from not only downloading new apps but also updating your current ones, on top of this you won't be able to take new photographs or add new music to you iPhone.
Often, going back and deleting tonnes of old images or general old files which you don't really use can be frustrating and tedious, while sometimes this is necessary, it can also be easily avoided.
Photographs can take up a large portion of memory. You tend to take multiple photos at once in the pursuit of the perfect shot, forgetting to go back and delete the ones which you are not going to use, this consumes memory and can easily be avoided by simply deleting unused photographs as you go.
Deleting songs you don't listen to is also a great way of freeing up memory, it is likely you won't listen to all of your music all the time, so just be selective and use what you're currently listening to. The same principle works for applications.
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