The Motorola Atrix 4G, flagship phone about a year ago, is now a great budget option if you need an unlocked and high performance Android phone. An NVIDIA Tegra 2 dual-core 1 GHz processor, 1GB of RAM, 16GB of built-in storage, micro SD slot, front and back cameras, a 1950 mAh battery (!) and more can be had for an affordable € 260 here in the Netherlands.

However, Motorola has cancelled the plans to upgrade this phone to Android 4.0 (ICS), so it’s stuck with its stock Android 2.3.4. It’s a fine ROM with great battery life, but Motorola probably won’t even ship incremental updates or bug fixes. There are know problems with Google Search updates FCing on app drawer, and newer versions of Google Maps getting confused with the relative priority of the GPS or network positioning.

It would be nice to have some options. This post briefly summarises the steps I took to root and unlock the phone, and my first impressions of CyanogenMod 7.2. The specific version of the phone that this post deals with is 45.31.0.MB860.AsiaRetail.en.03.

Warning: You follow these instructions AT YOUR OWN RISK. If by doing this you manage to break or brick your telephone, or you invoke any other calamity, the responsibility is entirely yours.

Screenshot of my Atrix 4G with CyanogenMod 7.2 and ADW.Ex Launcher.

To root the phone, take the following steps

  • Make sure your Windows installation has the Motorola USB and phone drivers installed. If you simply connect your phone with its stock ROM to the PC that you’re going to use, everything should be automatically installed.
  • Download fastboot from this XDA post, and unpack it in an easy to find directory, for example c:\moto.
  • Download the preinstall image from this XDA post, and put the unpacked .img file in the same directory.
  • Switch phone off, then on again with the volume down button held down. After a short while the phone says fastboot at the top: Now press volume up, it should say “starting fastboot protocol support”.
  • In a Windows command window, in c:\moto\, type: moto-fastboot.exe flash preinstall preinstall.img
  • After it’s done flashing, type: moto-fastboot.exe reboot
  • The phone will reboot now.
  • Download the android SDK from here and unpack the archive. Somewhere in there you should find adb.exe.
  • On the phone,  go to Settings |  Applications | Development and activate USB Debugging.
  • Disconnect and reconnect the phone to your computer. Drag down the phone notification area, tap “usb connection” then select “USB mass storage”.
  • Now you’re going to root the phone, by typing the following at the Windows command prompt:
c:\full\path\to\adb.exe\adb shell

The previous command should drop you into a $-style unix shell to your phone. At the $-prompt, type the following:

/bin/mount -o remount,rw /system
cp /preinstall/su /system/bin/
chmod 6755 /system/bin/su
PATH=/system/bin:$PATH pm install /preinstall/Superuser.apk

After all that, reboot the phone. It has now been rooted.

Unlocking and CyanogenMod 7.2

That was the difficult part. To unlock, simply follow the instructions under “Unlocking the Bootloader with RSD Lite (Windows)” in this CyanogenMod install guide, making sure to use the “International Variants Only: Unlockable Bootloader”. Once you’re done, move on to the part “Installing the ClockworkMod Recovery” and then “Flashing CyanogenMod”, the “Method via Recovery”. It’s all pretty straight-forward if you stick to the instructions.

First impressions

CyanogenMod 7.2 feels fantastically fast on this telephone, almost buttery. The fingerprint unlocker works much better than on the stock ROM, with the one caveat that you can’t have a pin-code-unlock backup. In other words, one unlock method can be active at a time. The battery unfortunately seems to drain quite a bit faster than with stock ROM. However, things seem to have become much better after one or two full charge-recharge cycles. Here’s my battery usage graph at about 29 hours after being taken from its charger:

Battery discharge graph at about 29 hours.

It was disappointing to discover that although the camera and camcorder work, the camcorder in portrait mode does not correctly orient the stored movie. I have not yet been able to find a work-around for this.

The phone feels really fast. Together with the flexibility that CyanogenMod 7.2 and being rooted give me (zillions of configuration options! if the XDA hackers manage to get the leaked ICS ROM into more solid shape, that upgrade is a tap away!), the trade-offs are, for the moment, acceptable.