Photos can stay on an old iPhone if they have not been deleted or transferred to another device. When you have photos on your iPhone, they are stored in the Photos app, and unless you manually delete them, they will remain on the device.
However, it’s important to note that the storage capacity of an iPhone is limited, and if you have a lot of photos or other data on your device, it may start to run out of space. In such cases, you may need to delete some photos or transfer them to another device or storage solution to free up space.
If you have iCloud Photo Library enabled on your iPhone, the photos on your device are also automatically synced to your iCloud account. This means that even if you delete a photo from your iPhone, it will still be available in your iCloud Photo Library and can be accessed from other devices connected to the same iCloud account.
To ensure that your photos are backed up and accessible even if you switch to a new iPhone or experience any issues with your current device, it’s always a good idea to regularly back up your iPhone to iCloud or iTunes. This will help you keep your photos and other data safe and easily transferable to a new device.
In my personal experience, I have encountered situations where I wanted to keep certain photos on my older iPhone while upgrading to a new device. In such cases, I made sure to transfer the photos I wanted to keep to my computer or another storage solution before setting up the new iPhone. This way, I could access those photos whenever I needed them, even though they were no longer on my old iPhone.
To summarize, photos can stay on an old iPhone as long as they are not deleted or transferred to another device. However, it’s always a good practice to regularly back up your iPhone and transfer important photos to another storage solution to ensure their safety and accessibility.