Microsoft’s $15 million investment in Foursquare will soon result in product changes in the coming months. Bloomberg News reports that the deal will be used for location data and services that are part of Microsoft’s upcoming Windows Phone 8.1 update. The software maker is currently beta testing a “Cortana” personal assistant in Windows Phone 8.1, named after the same character found in Halo. Foursquare’s data will help Cortana push out tips, discounts, and suggestions based on location.

While Microsoft isn’t commenting on Windows Phone 8.1 or Cortana, Microsoft’s Zig Serafin has revealed to Bloomberg News that Foursquare’s data will be used in future Windows Phone software. “We’re building some contextually aware experiences to power some upcoming products in Windows Phone,” Serafin said. “This will be for anywhere you get a Bing-powered experience.” Some recent rumors had suggested Cortana would be restricted to the US market initially, but it appears Microsoft will likely bring the personal assistant to countries where Bing is present.

Microsoft’s Cortana work in Windows Phone 8.1 is largely focused on context, rules, and signals. Data from alarms, calendar, weather apps, calls, and even whether a device is charging, can all be fed into the service to provide notifications and context around Windows Phone use. Early screenshots of Microsoft’s Cortana system showed that the company is testing location polling, and pulling data from Wi-Fi and Bluetooth. Home and work location data, and favorite contacts will also play a big part in Cortana, providing more relevant and improved search results.

Cortana coming to Windows Phone 8.1 in April

The voice-activated personal assistant is expected to debut in April as part of Windows Phone 8.1. Microsoft is still beta testing Windows Phone 8.1, and the software is expected to be finalized next month ahead of the Build developers conference in April. Microsoft is planning to release Windows Phone 8.1 to developers at Build or soon after, with updates coming to existing devices in the weeks and months following April. Nokia is currently preparing at least two Windows Phone 8.1 devices, codenamed Goldfinger and Moneypenny. The Finnish smartphone maker is planning a press event at Mobile World Congress later this month, but sources familiar with Nokia and Microsoft’s plans have revealed to The Verge that Windows Phone 8.1 devices will not be shown.

Microsoft is also holding its own Mobile World Congress press event on February 23rd. Windows executives will be in attendance, but we understand Microsoft isn’t planning to fully detail Windows Phone 8.1 at the show. It’s more likely that Microsoft will focus on Windows Phone momentum, and possibly unveil new Windows Phone partners for 2014. Sony has been rumored to be preparing a Windows Phone device, and any confirmation of that speculation at Mobile World Congress could help soften the blow of Sony’s VAIO sell off. Microsoft could also choose to highlight, at a high level, its plans for Windows Phone in 2014 and beyond, including its work towards merging Windows Phone and Windows RT.