There are two major details that make the OnePlus One ($300-$350) a game changer; Its hardware specs, and its software (CynongenMod Android 4.4.2 KitKat). Lets take a look at the software first.
CynongenMod is a modified version of Android. It has over 8 million users and has become a legitimate alternative to standard Android installations. CynongenMod offers options not found on the standard installs including; native theming support, FLAC audio codec support, a large Access Point Name List, an OpenVPN client, support for Wi-Fi, Bluetooth, and USB tethering, over-clocking, soft buttons and much more. The problem with was that you needed a certain level of technical knowledge to get the thing installed. The group behind the firmware have stated that one of the problems they are looking to overcome is the high install failure rate. OnePlus One has taken care of those issues by becoming the first smartphone manufacturer to have the software already installed on their phone.
The hardware for the OnePlus One matches up against phones that retail for twice the price. It goes for $300 for the 16GB and $350 for the $64GB version and features specs that match up with the Galaxy S5, HTC One M8, and Sony Xperia Z2 at half the price. It has a 2.5GHz quad-core Snapdragon 801 processor, 3GB of RAM, an Adreno 330 GPU, a 13 megapixel camera, and a 5.5 inch full HD 1080p display with 401 pixels per square inch.
Check out OnePluses forums for details on their invite process to get your phone.