Enable the SD Card while USB Debugging?

Question

I am developing a phone app and I'm testing it with my Droid RAZR with OS version 4.1.2

I need the phone to be able to use its SD card, and prevent the computer from using the USB connection as a "mass storage" connection, which causes it to take over the SD card (it can only be mounted to either my phone or the computer, not both).

You used to be able to connect to the computer in "Charge Only" mode, which would keep the SD card active with the phone, but that no longer seems to be an option. There is only Mass Storage (computer uses SD card), Media Device (same story), and Camera (same there too).

Is there another option? Perhaps some way to disable the mass storage from the PC's side but still retain the USB Debugging?

Answer 1

Take a look at this thread here. As stated there:

Next, enable USB debugging by checking the “USB Debugging” item.

Finally – and this is the most oddball – you need to go back a screen, to Settings, and click on the Storage item. Up in the upper right of the screen are three tiny squares which represent the Jelly Bean way of doing a context menu. Click that, and a small “USB Computer Connection” item will appear. Click that. You’re taken to a new screen with two “Connect As” options.

Check “Camera”. Yes, because USB debugging requires the use of a camera (no, not really). It’s just a requirement. Something about the communication protocol or file transfer encoding or something. I don’t make this stuff up.