Almost a year after it was established, startup phone manufacturer OnePlus may have lost its key partner in developing the OnePlus One smartphone. GSM Arena reported that OnePlus has silently taken out the Cyanogen branding from its flagship smartphone.

When the smartphone was unveiled in March, the startup company proudly announced its partnership with one of Android's most popular ROM developers. Based on updated statistics in CyanogenMod's database, the ROM already has more than 16 million downloads across devices and Android versions.

While the move does not automatically mean Cyanogen will not work together with OnePlus in future projects, the report showed that for upcoming shipments of OnePlus One, those smartphones will not run CyanogenMod anymore.

Last week, Cyanogen's CEO Kirt McMaster announced in an event in California that his company is planning to break away from Google and its services. Moreover, he said that Cyanogen will soon partner with other smartphone brands and developers in order to provide a smoother Android experience to CyanogenMod fans. 

Meanwhile, OnePlus will unveil a brand new Android ROM that will power its OnePlus One smartphones this month. In the report, the custom ROM dubbed Oxygen will be based on Android 5.0 Lollipop and is "open, customizable, and free of bloat and unnecessary features." 

OnePlus first introduced the OnePlus to the world around February last year and referred to it as a 'flagship killer', pertaining to other high-end smartphone brands at that time, which include the Samsung Galaxy S5, Sony Xperia Z2, and the LG G Pro 2. 

Unfortunately for OnePlus, its invitation system failed to sell the device effectively to interested consumers. In a report by Forbes last year, the company aimed for the OnePlus One to sell one million units in 2014. 

The OnePlus One first gained popularity as a high-end handset that was only sold for less than $349. Some of its specs include a 5.5-inch display with Full HD (1920 x 1080) resolution, a Snapdragon 801 chipset, quad-core CPU clocked at 2.5GHz, 3GB ofRAM and 64GB of internal storage. Other specs include a 13MP primary camera, and the option to swap back covers.