A Quick Guide To Android USB Connections (USB Mass Storage, PTP & MTP)

When you connect your Android to a computer, it will use one of three protocols: USB mass storage, PTP or MTP. Read on to find out more about what this all means.

A Quick Guide To Android USB Connections (USB Mass Storage, PTP & MTP)

When you plug your Android phone into your computer’s USB port, you probably don’t think too much about it, but there’s a lot going on to make sure that data is transferred between the two. An important part of this process is the type of USB connection being used.

Nowadays, you can choose which protocol to use when you connect your Android device to a computer: MTP or PTP. Before this though, all connections were made via the USB mass storage protocol.

Selecting a USB connection protocol

If you have a new enough device, you can choose between the MTP and PTP protocols. This can be done in your device’s Settings menu. When in the menu, go to Storage then tap on the 3 dots in the top right-hand corner. In the drop-down menu that appears, tap on USB computer connection.

Some devices allow you to select a USB connection protocol

This will show you the USB connection protocol that your device uses, and let you change it the option is available.

USB mass storage

The USB mass storage protocol was (and is, if your device is old enough) used by older Androids when connecting to a computer. When this protocol is used, you need to confirm the connection by pressing Connect storage to PC and connecting it via USB cable. When disconnecting you’ll need to press Turn off USB storage.

This is the same protocol that external hard drives, pen drives, SD cards and other storage devices use when connecting to a computer. When this connection is used, the external storage essentially functions as internal storage while it is plugged into the computer.

During that time, the external storage device can’t be used for anything else. For a pen drive or an SD card, that’s fine. For your mobile phone, less so. It essentially means you can’t do anything with your Android device while it is connected to a computer. No calls, no texts, no Clash of Clans!

It also means that the device has created separate partitions in storage for the system and for the USB connection. This wastes a lot of space.

It’s no wonder that Androids have moved on to using other USB connection protocols.

Media Transfer Protocol (MTP)

Instead of appearing as a storage device when connected to a computer (as in USB mass storage), this protocol shows your Android as a media device. USB mass storage lets the connected computer access your phone’s raw file system, while MTP just gives it a list of files instead.

In this scenario, when you transfer a file from your phone to your computer, the computer has to make a request for the file that is being transferred. It can’t just take the file the same way it does when using USB mass storage.

This protocol also allows use of file systems other than the FAT32 system used by windows. The main example is ext4, which is faster than FAT32.

When using MTP to transfer files between your phone and your PC, you won’t really notice any difference from USB mass storage. The interface and processes involved will appear the same.

Picture Transfer Protocol (PTP)

When using this protocol, the computer reads your device as a digital camera. As you can guess from the name, this protocol was created for transferring photos from a digital camera.

You can use this protocol when working with programs that don’t support MTP. Other than that, it’s best to stick with MTP, given the choice.