Less than a week after the release of ChevronWP7, which allows you to unlock any retail Windows Phone 7 device for application side-loading without having to pay $99 per year for a WP7 marketplace account, the app has been discontinued. ChevronWP7's three developers, Long Zheng, Rafael Rivera, and Chris Walsh were approached by Brandon Watson, Director of Developer Experience for Windows Phone 7, and decided to kill their app.

"Through this discussion, we established a mutual understanding of our intent to enable homebrew opportunities and to open the Windows Phone 7 platform for broader access to developers and users," the developers said in a statement. "To pursue these goals with Microsoft's support, Brandon Watson has agreed to engage in futher discussions with us about officially facilitating homebrew development on WP7. To fast-track discussions, we are discontinuing the unlocking tool effective immediately."

Zheng, Rivera, and Walsh will likely become more involved with the shaping of the Windows Phone platform but ChevronWP7 will not be the way to do so. The app caused a lot of controversy as the developers argued with Microsoft and bloggers in regards to the unlocking process and potential piracy applications.

In the meantime, the trio has made available a WP7 custom ringtone manager (download tool, download source) the first WP7 homebrew application taking advantage of unlocked phones. The application has two components: desktop, used to build a custom XAP package with five custom ringtones you select from your computer (requires .NET 4.0 Framework), and XAP, deployed to your WP7 device to install the custom ringtones. Ringtones have to be in the WMA format at 48KHz (a WP7 requirement). Also, the XAP has to be deployed using the Microsoft Application Deployment tool with the Windows Phone 7 Developer SDK.