Nokia this week unveiled the 4.7-inch Lumia 625, the company’s largest Lumia smartphone to date. A new leak may confirm earlier reports, however, that Nokia is looking to go even bigger. An image published recently by anonymous industry insider C Technology revealed what is said to be the front panel from an upcoming 6-inch Lumia smartphone. The device is reportedly in mass production and is expected to launch later this year with the Windows Phone 8 GDR3 update, which will add support for full HD 1080p displays and quad-core processors. The leaked image follows below.