Which Android phones will operate as an external drive for PC files?

[Steven Lyle Jordan]

I use my current phone (Droid 4) to store work and personal PC files as an external drive... which I'll plug in to my PC at work or at home, and open the files from the phone onto my PC. I know current phones and devices will carry and transfer the files, but will all of the Android phones allow me to access their stored files from the PC and directly open them (without having to transfer them to the PC)? Phone data and descriptions I've seen have been very vague on the subject.

 

[B. Diddy]

Welcome to Android Central! When connected via USB and using the MTP protocol, your computer can open files (like text files and photos) directly from the phone. I just tested it on my Nexus 5.

Mounting a phone as a USB Mass Storage device requires the phone's Internal Storage to be partitioned into at least two areas, the first being the protected system partition that also includes where you install apps, and the second being an "Internal SD" area which acts like an SD card. It's the Internal SD part that gets mounted as USB Mass Storage when you connect to the computer. But the big problem with this is that it severely limits how many apps you can install on the phone, since the protected system/app installation partition is generally pretty small. For example, with my old Razr Maxx, you were limited to about 3 GB of app installation storage space, on a phone that came with 16 GB of internal storage. Thankfully, this kind of setup was abandoned around the time of ICS or Jellybean.

 

[Steven Lyle Jordan]

Thanks! I've heard elsewhere that only devices with SD cards can do this. However, I have a Lenovo tablet which has an SD card, but won't allow you to open files on the PC... hence, my concern. I'm considering replacing my Droid with an LG V10 or Samsung S5 (because I like the landscape modes), but I want to be sure whatever I get will allow me to open files.

 

[B. Diddy]

When you connect that Lenovo tablet to the computer, you can't open any files at all? Or just files on the microSD card?

 

[Steven Lyle Jordan]

As an example, I can open a Word doc in Lenovo storage on the PC, but only as read-only. I cannot save a Word doc (or any other type of file) to the Lenovo; I have to save the doc to the PC and manually copy or move it to the Lenovo in File Manager. This goes for internal memory as well as the SD card. In contrast, I can open files in Droid 4 storage (internal or SD card) on the PC as editable, and save them directly to the Droid from the PC, without going through File Manager.

 

[B. Diddy]

Oh, I see. I didn't try editing a Word doc--only a .txt file. I can try doing that on my devices as a test.

 

[Steven Lyle Jordan]

Long story short, my Droid 4 died, bought a Droid Turbo 2. I've just tried to open a Word file stored on the phone, using the PC through the USB connection. Word on the PC won't allow you to open the file from the phone: Though you can navigate to the file and see it, when you click "open" the filename in the lower display changes to "{00003DBD-0001-0002-0000-000000000000}". (And somewhere, Vincent Price's maniacal laugh drifts over the cubicles.)

When I try to save a Word file to the phone, I navigate to the folder, click "save"... and the Save As screen greys out. You can click "cancel" to escape, but that's all you can do. (Vince laughs again.)

My Droid 4 could do this trick; it's one of the few things I wanted to be able to do with a new device, and it's let me down. Not. Happy.

 

[B. Diddy]

It sounds like this is a limitation of MTP, vs the old method of making the phone's Internal SD mount as USB Mass Storage.

I doubt this will help, but see if it helps to change to PTP. (PTP is Photo Transfer Protocol, developed for cameras--so it probably won't work either.)

 

[Steven Lyle Jordan]

Yeah, I confirmed that the PTP protocol didn't work either.

Further research has suggested to me that the formatting might be an issue: The SD card is FAT32, but when the card is in the phone, and viewed from the PC's file manager, the format is listed as "generic hierarchical." So maybe the PC is having trouble figuring out this format type when opening and saving PC files?

A post in AndroidForums, "Format SD Card FAT32", suggests it might be a driver issue (hopefully at the PC end). Any of this sound likely?

 

[B. Diddy]

I don't think the fact that the card is in FAT32 should matter--FAT32 is pretty much universally compatible. Driver issue is always possible. You could try reinstalling Motorola Device Manager, which should include the current USB driver: https://motorola-global-portal.custhelp.com/app/answers/prod_detail/a_id/103535/p/30,6720,9277

 

[Steven Lyle Jordan]

I don't think the fact that the card is in FAT32 should matter--FAT32 is pretty much universally compatible.

Yes; but the fact that my PC doesn't recognize the SD card in the phone, nor the phone's internal drive, as FAT32 sounds significant. (I just checked: My Lenovo tablet's internal drive and SD card are also recognized by the PC as "generic hierarchical," and just like the phone, it also won't let me directly open its stored files on a PC.)

I'll try updating the driver when I get home, but this seems like a problem between Windows and Android, not Motorola products.

 

[Steven Lyle Jordan]

Update: I loaded the driver, but it had no impact... nothing's changed.

 

[B. Diddy]

Ah durnit. Sorry, running out of ideas. I suppose you could try an SD card that's formatted in exFAT or NTFS, but these formats are less likely to be compatible with the phone.

 

[Steven Lyle Jordan]

I did try formatting the card in exFAT, but it made no difference. I also tried giving it a new name (using ES File Manager), but the name doesn't take.