The drivers and phone is capable like any other - Not officially, plugging devices into the phone will not work, nor windows wont give you full host access with out using mass storage mode.
There is a little application called Droidexplorer which works in a similar fashion to otg, but also allows access every part of the phone (root) when simply plugged in even when the phone is set to charge only mode.
Excellent app if this is what your looking for, look it up.
OTG works perfectly with a modded lapdock, with the keyboard, touchpad and 2 USB ports all interfacing via USB. The stock ROM even supports mounting and unmounting flash drives as shown by a screenshot in this post: http://forum.xda-developers.com/show...3&postcount=29
But I could never get it working with an OTG adapter. That same OTG adapter works fine on my Touchpad so thats not the issue. Its possible that the Droid 3 needs +5v Vcc to be connected, because when its on the lapdock its charging as well as providing OTG. This is different from my Touchpad which refuses to charge when in OTG and doesn't even need Vcc connected.
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