The apps will be compatible with Outlook, Outlook.com and Office 365.
Microsoft is reportedly planning to allow third-party developers to create add-ins and apps for its Outlook.com email service.
The revelation was made by the company posting descriptions for its Build 2015 developer conference, which begins tomorrow.
It said: "Yes, you read that right – in under 5 minutes, you can build one app, list it in one store and have it appear in Outlook.com, Outlook desktop and Office 365.
"We’ve got many exciting updates since Build 2014 – from apps platform coming to Outlook.com, to simple development tools, to apps now able to place buttons among native Outlook actions.
"Learn about new capabilities, new UI entry points and best practices for building beautiful and powerful integrations via Apps for Outlook."
According to reports, Microsoft is planning to give developers the tools to make a single app that will be capable of running on Outlook, Outlook.com and Office 365, resulting in creation of consumer-friendly apps and services for Outlook.com.
Presently, apps and add-ins are available for the Office 365 version of Outlook, but apps for Outlook only work with the Office 365 and targets enterprises.