Jolla, the Finnish smartphone startup steered by ex-Nokians, has teamed up with the design firm behind Nokia's E-Series device line.

Infinity, a Finnish design company, has been working with Jolla for the past six months on the design of Jolla's forthcoming device using its MeeGo-based Sailfish OS , it announced on Monday.

The company has not shared any details about what the device it's working with Jolla on and would not disclose how many models it has been contracted to design when contacted by ZDNet.

Jolla is working on its own Sailfish smartphone while also allowing Sailfish OS alliance partners to build their own devices around the platform.

Infinity's history in mobile design includes work on Nokia's E-Series phone , as well as more than 50 Nokia headsets and chargers, according to Infinity's CEO, Mikko Kämäräine.

"We worked extensively on E-Series and were the subcontractor that helped design that," Kämäräine told ZDNet.

More recently, Infinity has designed a number of Huawei's smartphones for the Chinese market and its new Android Ascend , launched at this year's Mobile World Congress, according to Kämäräine.

Huawei for its part has been investing more in Finland, late last year committing to €70m over five years to establish a smartphone R&D facility in Helsinki for its Windows and Android devices.