The Windows 10 Technical Preview was released this Thursday, but only for select phones. Now thanks to an XDA-Developers hack you can install it on just about any Lumia that you are not using. That last bit is important since this can brick your device. People have reported success with various phones, including the Lumia 720, which has just 512MB RAM. The update is officially available for 512MB phones, though there’s a possibility they won’t"XDA-Devs find way to install Windows 10 on any Lumia"