This post is kept for historical purposes. A new version has been released, called Orientation Lock, which is device independent and works much better.

I've spent the last few days trying to figure out what's up with that posture when one uses a phone while laying down. Whatever the deal is, it always manages to trigger the accelerometer, and that's flat out frustrating. So here's a little something for people who want to stop their accelerometer's from rotating the screen.

This application is very, very simple. It finds the handle of the accelerometer, and then sends a close device command to it. Because it uses drivers, IDCAPINTEROPSERVICES is required, and thus, your phone must be interop unlocked. This narrows down the supported devices list, which is further narrowed down by an apparent change in how HTC handles the drivers. I'm looking into it, but for now, here's how it looks:

Requirements

Interop unlocked device

Supported devices

LG and Samsung confirmed

HTC isn't currently supported. Looking into it.

Features

What it does: Disables the accelerometer. That means all accelerometer activities will be stopped until you reboot your device.

It does not lock the orientation specifically, but the orientation won't change when the accelerometer is disabled.

Download: (Do not redistribute or hotlink; link to this page instead)

acceldisable1.xap

Also, please comment on whether it works for your device or not; if you have HTC and it works, let me know. If you have HTC and it doesn't work, I already know that, so you can save your bandwidth ;)

Enjoy! 

~Jaxbot