As Nokia plans to unveil two additions to Lumia Windows Phone line on Wednesday, we have learned of another device that the company is currently testing. According to sources familiar with Nokia's Windows Phones, the Finnish manufacturer is preparing a handset codenamed "Glory" that will include a 4-inch display.

The handset is designed as a successor to the low-end Lumia 610 "Tango" Windows Phone and will include Windows Phone 7.8 and low specifications such as a 800mhz processor and the typical 256MB of RAM found in super low-end Windows Phones. We understand that the handset could launch as early as the holiday season — but that the availability date has not been fully determined. We don't expect Nokia to unveil the Glory at its special Windows Phone event next week, where the company will unveil the Lumia 920 and Lumia 820 handsets.