Rumours suggest Nokia's big Mobile World Congress (MWC) announcement will be the unveiling of its final Symbian smartphone, the Nokia 803.

According to tech site BGR, Nokia's final Symbian smartphone will be the company's primary offering at this year's MWC. Not letting a lack of official word get in the way, BGR also alleged to have ascertained a number of details regarding the mysterious device's tech spec.

Specifically, BGR reported that the a number of unnamed sources had confirmed the Nokia 803 would be released running Symbian Belle packing a 4-inch AMOLED display, HDMI-out port, microSIM support, NFC and - gilding the lily - boast the largest camera sensor ever seen on a mobile phone.

Though Nokia hasn't confirmed any of this, the 803 is generally believed to be set for a May release. It will reportedly be the last smartphone running Nokia's home-grown Symbian operating system. The OS has gradually been phased out since Nokia made a deal with Microsoft to have its devices run using the company's Windows Phone OS.

To date Nokia has released a number of devices running on Windows Phone, including the flagship Lumia 800, which was released in the UK to a moderately positive reaction at the end of 2011.