External storage for iPhone 14 and older
Sandisk's iPhone storage page covers iPhone 15, 16 and 17, the USB-C models. If you have an older iPhone, a USB-C drive won't fit the port.
Options with hardware
Lightning flash drives and card readers exist, usually Apple MFi certified, and Apple sells a Lightning to USB camera adapter. They cost money and one more thing to carry.
Option without hardware
Pair the iPhone with a spare device in the browser and send files over Wi-Fi. SpareDisk works on any phone with a modern browser, Lightning or not.
Speed
Lightning on iPhone 14 and earlier runs at USB 2 speeds. Wireless speed depends on your Wi-Fi.
Try it with the two devices you have
Open SpareDisk on both, scan the QR code, type the reply code, and send. Free to start, no account.
Open SpareDiskQuestions
Can I plug a USB-C drive into an iPhone 14?
Not directly. It has a Lightning port, so you'd need a Lightning drive or an adapter.