Almost every Android phone can use a USB drive directly — no computer, no special app. Plug a drive in, and it shows up in your file manager like another folder.
The feature that makes this work is called USB OTG. This guide explains what it is, what you need, how to find and remove a drive, what you can do with one, and how to use it for the job most people want it for: backing up photos.
What is USB OTG?
USB On-The-Go (OTG) is a standard that lets a phone act as the host of a USB connection.
Normally, when you plug a phone into a computer, the computer is in charge and the phone plays the role of a device. With OTG, the phone takes charge: it powers the accessory and controls it. That's what lets a phone read and write a flash drive — and it's also why OTG works with other accessories, like card readers, keyboards, mice, and game controllers.
Does your phone support it? Nearly every Android phone made in the past decade does, and any phone with a USB-C port almost certainly does. A few budget models leave it out. The quickest test is simply to plug in a drive.
What you need
A drive with the right plug:
- USB-C flash drive or SSD — plugs straight into any USB-C phone. Dual drives with both USB-C and USB-A plugs are handy for moving files between a phone and a computer.
- A drive with a USB-A plug (the older, rectangular type) — needs a small USB-C OTG adapter.
- Older phones with micro-USB — need a micro-USB OTG adapter.
A cable or adapter that carries data. Some USB-C cables and cheap adapters carry only power. They look identical, and they're the most common reason a drive doesn't show up.
Enough power for the drive. Flash drives and small SSDs are fine. Portable hard drives often need more power than a phone supplies — use a powered USB hub.
How to connect a drive and open it
- Plug in the drive. Most phones show a notification when it connects.
- Open your file manager. In Files by Google, the drive appears under Browse. In Samsung My Files, it appears as USB storage.
- Browse it like any folder. You can also see it under Settings → Storage on many phones.
Some phones need OTG switched on. On many OPPO and Realme phones there's an OTG connection setting under Settings → Additional settings, and OnePlus phones have a similar OTG storage setting. On these phones it switches itself off after about ten minutes of inactivity. If your drive doesn't appear, see Android phone not detecting your USB drive?
What can you do with a USB drive on Android?
- Copy photos, videos, and files in either direction — from phone to drive, or drive to phone.
- Free up space by moving large files, such as old videos, onto the drive.
- Play videos and music directly from the drive.
- Open documents — PDFs and other files open from the drive in the apps you already use.
- Move files between phones or to a computer without uploading anything.
- Read camera memory cards using an SD card reader.
Copy, don't move, when it matters. "Move" deletes the original as it goes, so an interrupted move can leave a file on neither the phone nor the drive. Copy first, check the copy, then delete the original.
Which format should the drive be?
exFAT — it works on most current Android phones, as well as on iPhone, Windows, and Mac, and has no practical file size limit.
- FAT32 also works, but it can't store any single file over 4 GB, so long videos fail to copy.
- NTFS, common on drives used with Windows, is often read-only on Android.
- Mac and Linux formats generally aren't supported.
Android can format a drive under Settings → Storage, but which format it uses varies by phone, and some choose FAT32. For a backup drive, formatting as exFAT on a computer is the reliable route. exFAT vs FAT32 for phone backups covers the details. Formatting erases the drive, so copy anything important off first.
How fast is it?
It depends on the phone's USB port and the drive. Many flagship phones support USB 3 speeds, while many budget phones are limited to USB 2. A portable SSD is usually much faster than a basic flash drive — a difference you'll notice when copying a whole photo library.
How to remove the drive safely
- Let any copy finish.
- Eject the drive — most phones offer Eject in the notification that appeared when it connected, or under Settings → Storage.
- Unplug it.
Neither exFAT nor FAT32 is designed to survive being unplugged mid-write, so a drive pulled out during a copy can end up with a damaged file — or occasionally a damaged folder structure.
Using a USB drive to back up your photos
The most common reason to connect a drive is to back up photos and videos. You can do it by hand with your file manager — copy DCIM/Camera, then the other folders where media lives — and for a single folder, that's fine.
For a whole library, VaultDrive makes the connection do the work:
- It finds all your media, not just the camera folder — screenshots, other apps' folders, and with Pro, WhatsApp media — and mirrors your phone's folder structure on the drive.
- Choose the drive once. VaultDrive keeps permission to the drive you picked, so later backups go straight to it.
- It checks the drive's format and warns you about FAT32, NTFS, read-only drives, and unsupported formats before you start.
- It runs with the screen off, with progress, pause, and cancel in a notification.
- A disconnect doesn't cost you the backup. If the drive drops out, Reconnect & Resume picks up where it stopped, and files are written whole or not at all.
- Every copy is checked against the original, and one bad file doesn't stop the run.
- With Pro, later backups copy only what's new, so keeping the drive current takes minutes.
It's free for up to 200 files or 2 GB per backup, and Pro is a one-time purchase. The full walkthrough is in how to back up Android photos to a USB drive, and the built-in file manager is compared with VaultDrive in file manager vs VaultDrive.
Using an iPhone as well? The iPhone version of this guide is can you connect a USB drive directly to an iPhone?
Frequently Asked Questions
Can I connect a USB drive to my Android phone?
Yes. Nearly every Android phone made in the past decade supports USB OTG, which lets it read and write a USB drive directly. A USB-C flash drive plugs straight into a USB-C phone, and a drive with the older USB-A plug connects through an inexpensive OTG adapter. The drive then appears in your file manager.
What is USB OTG?
USB On-The-Go is a standard that lets a phone act as the host of a USB connection. Normally a phone plays the device role when connected to a computer. With OTG it can power and control USB accessories itself, including flash drives, SSDs, card readers, keyboards, and mice.
Do I need an adapter to use a USB drive with Android?
Only if the plugs don't match. A USB-C flash drive or SSD connects directly to a phone with a USB-C port. A drive with a full-size USB-A plug needs a USB-C OTG adapter, and older phones with a micro-USB port need a micro-USB OTG adapter. Make sure any cable or adapter carries data, not just charge.
How do I find the USB drive on my Android phone?
Most phones show a notification when a drive connects. The drive also appears in your file manager: under Browse in Files by Google, or as USB storage in Samsung My Files. Many phones list it under Settings then Storage as well. If it doesn't appear anywhere, the cable, an OTG setting, power, or the drive's format is usually to blame.
How do I safely remove a USB drive from Android?
Wait for any copying to finish, then eject the drive before unplugging it. Most phones offer Eject in the notification that appears when the drive connects, or in Settings under Storage. Unplugging mid-copy can damage the file being written and occasionally the drive's folder structure.
What format should a USB drive be for Android?
exFAT. Most current Android phones read and write it, it also works on iPhone, Windows, and Mac, and it has no practical file size limit. FAT32 works too but can't store any file over 4 GB, so long videos fail to copy. NTFS drives are often read-only on Android.
The short version
USB OTG lets your Android phone power and control a USB drive directly. Use a USB-C drive, or a USB-A drive with an OTG adapter — and make sure the cable carries data. The drive appears in your file manager; eject it before unplugging.
Format it exFAT, and it'll work with your phone, an iPhone, and any computer. For backing up your whole photo library to it, VaultDrive finds every folder, checks the drive's format, runs with the screen off, and resumes if the drive drops out.