Nokia is restructuring its devices and services business into three units amid shareholder discontent and struggles to develop relevant challengers to popular smartphones like the Apple iPhone.

Under the new, “simplified” company structure, Nokia’s devices and services business will be comprised of three units: Mobile Solutions, Mobile Phones and Markets.

The solutions unit will handle the company’s high-end device portfolio, including the MeeGo and Symbian operating systems. The unit will be headed by Anssi Vanjoki.

As part of the solutions unit, Tero Ojanpera will work on development of Nokia’s Ovi service into smartphones and mobile computers.

The phone unit will be led by Mary McDowell and is aimed at maintaining Nokia’s lead market share in the handset space and will handle its lower-end Series 40 phones.

Nokia’s new markets division will be responsible for Nokia’s “go-to-market” activities, including sales and marketing, management of Nokia’s global supply chains and sourcing operations.

Nokia CEO Olli-Pekka Kallasvuo said the new organization structure was designed to “speed up execution and accelerate innovation.”

“We believe that this will allow us to build stronger mobile solutions – a portfolio of products and integrated services that connect people and enable new ways of communicating, sharing and experiencing mobility,” he said in a statement.

As part of the restructuring, Nokia announced the retirement of Rick Simonson, who was appointed to lead the company’s handset division last October.

The company’s reorganization becomes effective July 1. As of that date, the company’s executive board will consist of the following members: Olli-Pekka Kallasvuo, Esko Aho, Juha Akras, Timo Ihamuotila, Mary McDowell, Kai Oistamo, Tero Ojanpera, Niklas Savander, Alberto Torres and Anssi Vanjoki.