Donovan Colbert walks you through the steps of modding the Motorola Atrix Lapdock so that it's compatible with the Droid 4.
Recently, I saw the Motorola Atrix Lapdock on closeout for $59. I hesitated and missed that deal, but a few days later, another site offered the Lapdock for $69. A quick Google search showed that with a simple hardware modification, the Droid 4 was compatible, so I jumped on it. This worked great while camping over the Memorial Day weekend when I forgot the charger for my TF300 at home. I was able to keep connected and enjoy a full desktop browsing experience and wireless connectivity through my docked phone.
The mod is simple. The orientation of the USB and HDMI ports on the Atrix are flipped on more recent phones. You just turn the orientation of the connectors 180 degrees, and that unlocks access to the Webdock mode of your Droid 4. Being that the very similar Motorola Lapdock 100 still retails for $250, this isn't a bad deal if you're willing to void your warranty and risk destroying a $70 piece of equipment.
The significant difference here is that the touchpad on the Atrix Lapdock does not support multi-touch gestures. Keep in mind that neither TechRepublic nor I are responsible for any damage you cause to your phone, your Lapdock, or yourself while attempting to perform this hardware modification. Proceed at your own risk.
First, gather the tools that you'll need.
A small Phillips head screwdriver.
An Exacto knife. A pair of tweezers or small needle-nose pliers are also a good idea to have on hand.
Open the cradle on the Lapdock. There's an adaptor plate you can remove and put aside. You won't need it again. On each end of the cradle is a small black sticker covering a screw. Pry the dots off with the tip of your knife, and put them aside for later.
Once the sticker is removed, remove the screw. Place the screw aside for reassembly. Repeat this for each side of the cradle.
Once the two screws are removed, pry the cradle open along the top lip. I used a small flat metal "spreader" to unsnap the top assembly from the bottom of the cradle. This will reveal the HDMI (on the left in the picture above) and the USB connectors held in place by a metal bar screwed into the top assembly of the cradle.
The cable for the HDMI is attached to the left screw by a piece of reinforced fabric that broke for me during the reassembly process. There's also a rubber spacer between the HDMI and USB cable. Remove the screws and place them aside. Pry off the metal bar and place it with the screws. The rubber spacer is firmly held between the two connectors. I took the sharp end of a pencil and pried it toward me. Once you've removed the spacer and placed it with the other parts, gently remove the connectors from the top assembly of the cradle.
The top assembly will now be free of the dock. Take your exacto knife and carefully trim the edges that face the front of the Lapdock when the cradle is in position for a phone. This will allow you to flip the ports orientation so that they'll work with your Droid 4.
A note of caution here: On my first attempt, I didn't trim the plastic aggressively enough. This caused the USB port to sit at a slight angle and prevented it from protruding far enough through the top of the cradle when I reassembled it. This in turn caused the Lapdock and Droid 4 to occasionally fail to connect to one another or to disconnect an active session. After disassembling the cradle again and doing a little more trimming on the USB port opening, I was able to resolve this issue.
Now, simply flip each connector 180 degrees. Insert them in the trimmed holes on the Lapdock with the rubber spacer between them. As you look at the cradle from the front of the Lapdock, the USB is on the left and the HDMI is on the right. This does not change. You flip the actual connector, but they still retain the same orientation to one another after the mod.
Screw the metal bar back in place and make sure the wires are routed so that they won't protrude from the bottom of the cradle once you put it back together. Snap it back into place, and replace the screws that hold the top and bottom assembly of the Lapdock cradle together. Replace the black dots, and connect your Droid 4. In a moment, the Mobile View screen should appear and you can launch Firefox from the Application dock at the bottom of the screen.
Here is the Droid 4 running desktop Linux Firefox on the Atrix lapdock.
This is a rear view of the Droid 4 docked in the Atrix Lapdock.
If you have any questions, ask in the forum, and I'll be glad to help if I can.Thanks to XDA-Developers forum member Nowell29 for posting the original screen shots and guide I used when modding my own Lapdock.