DJ Koh, president and CEO of Samsung Electronics, shakes hands with Satya Nadella, CEO of Microsoft, at a launch event for the Samsung Galaxy Note 10 smartphone in New York on August 7, 2019.

At the end of third quarter, Microsoft CEO Satya Nadella said the company had 200 million Office 365 commercial monthly active users. It's been investing heavily in developing and marketing Teams, which competes with Slack .

Microsoft set the stage for the Samsung agreement last week in announcing a push-to-talk feature in Teams and said it will be available to a limited set of customers in the first half of the year. The focus is on Android.

Samsung is the No. 2 seller of smartphones in the U.S. behind Apple , which has built its lead with the help of enterprise functionality like security and identity management. Microsoft has largely given up on handsets and ditched its smartphone operating system, but the company still has a big play in mobile through its cloud-based Office 365 suite, which includes Word, Excel, PowerPoint and Teams.

On Sunday, Samsung introduced the Galaxy XCover Pro, a smartphone with a push-to-talk button that initiates a chat using Microsoft's Teams app. It's a joint effort by the two tech giants to get their mobile technology in the hands of more workers who spend their days and nights navigating hospital hallways, supermarket aisles and airplane cabins.

Emma Williams, Microsoft's corporate vice president for Office verticals, said that in adding useful features for Teams, the company is trying to give people a more secure tool for chatting with co-workers than many of the consumer apps that are used in the workplace, whether it's Facebook's WhatsApp or Tencent's WeChat.

It also cuts down on the number of devices people have to lug around. Williams said that while shopping at a retailer over the holidays, she saw a man carrying a personal phone, a work phone a walkie-talkie and a pager on his belt.

"The product we're shipping extends the range of traditional walkie-talkie communication," Williams said in an interview. "It reduces licensing and provisioning costs, and it's one less device for the employee to carry."

It's not Microsoft's first swing at the market. In 2017, the company announced a bundle that included Office and other products for what it calls firstline workers in services industries and at task-oriented jobs. Late last year, Microsoft announced a new folding smartphone that runs on Android, but it's launching the new service with Samsung, which has a giant handset business and previously released a tablet for mobile workers.

The 6.3-inch Galaxy XCover Pro has a replaceable battery and can survive falls from as high as 1.5 meters, or about 4.9 feet. Taher Behbehani, head of the mobile business-to-business unit for Samsung Electronics America, said the device is rugged but designed to look sleek. It runs Android and Samsung's Knox security software.

The push-to-talk button on the phone initiates a conversation immediately. If the person on the other end doesn't have the device, there's a soft button within the Teams app that can launch the chat. Samsung designed the physical buttons so they can be customized, meaning they don't have to use it for Teams, Behbehani said.

Long ago, Microsoft had big ambitions in mobile hardware, acquiring Nokia's devices and services business in 2013. The company scaled back, taking billions in charges on the deal and selling off the handset business. It also stopped developing new features for Windows 10 Mobile.

Microsoft and Samsung said in August that Samsung devices would gain new integrations with Microsoft services like Outlook.

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