Connect external devices or servers with Files on iPhone
You can use the Files app to access files stored on external devices or servers, such as USB drives and SD cards, file servers, and other cloud storage providers like Box and Dropbox, after you connect them to your iPhone.
Connect a USB drive or an SD card
Insert a USB camera adapter or an SD card reader into the charging port on iPhone.
Do one of the following:
Connect a USB drive: Use the USB cable that came with the USB drive to connect the drive to the camera adapter.
Insert an SD memory card into the card reader: Don’t force the card into the slot on the reader; it fits only one way.
To view the contents of the device, tap Browse at the bottom of the screen, then tap the name of the device below Locations. If you don’t see Locations, tap Browse again at the bottom of the screen.
To disconnect the device, simply remove it from the connector on iPhone.
Connect to a computer or file server
Tap at the top of the Browse screen.
If you don’t see , tap Browse again.
Tap Connect to Server.
Enter a local hostname or a network address, then tap Connect.
Tip: After you connect to a computer or file server, it appears in the Recent Servers list on the Connect to Server screen. To connect to a recent server, tap its name.
Select how you want to connect:
Guest: You can connect as a Guest user if the shared computer permits guest access.
Registered User: If you select Registered User, enter your user name and password.
Tap Next, then select the server volume or shared folder in the Browse screen (under Shared).
To disconnect from the file server, tap next to the server in the Browse screen.
For information on how to set up your Mac to share files, see the macOS User Guide Set up file sharing on Mac.
Add a cloud storage service
Download the app from the App Store, then open the app and follow the onscreen instructions.
Open Files, then tap Browse (at the bottom of the screen).
Tap More Locations (below Locations), then turn on the service.
To view your contents, tap Browse at the bottom of the screen, then tap the name of the storage service below Locations. If you don’t see Locations, tap Browse again at the bottom of the screen.