Microsoft doubled down Wednesday on its message that Windows apps can work on a PC, smartphone or Xbox One during Build 2016, its annual developers conference in San Francisco. The tech giant used the Windows 10 Anniversary update to open the operating system to developers. Chatbots and Cortana were also featured prominently as a potential future for Microsoft in a world that has left the desktop behind.

"I am an optimist," Microsoft CEO Satya Nadella said during the Build 2016 keynote. "We, as a company, are optimistic about what technology can do for us. I believe technology can, in fact, drive economic growth all over the world. I believe technology can empower us in our daily lives. I believe technology can be used to preserve our enduring values."

Prior to delivering news about the future of Windows 10, Microsoft provided some sales figures for what it calls the "fastest growing version of Windows." Since its launch eight months ago, Windows 10 has been installed on more than 270 million devices. The highly anticipated Windows 10 Anniversary update, previously known as "Redstone," will launch in the summer. The Windows 10 update will further integrate Windows Hello, Microsoft's biometric authentication system, for apps, Windows Edge and supported websites. After the update, users can, theoretically, use their fingerprints to sign into their bank's website.

"The really interesting new piece from Build 2016 was the formalization of the Conversation as a Platform model. This is a pretty powerful concept and an opportunity for Microsoft to restore relevance with developers," Gartner analyst Steve Kleynhans told International Business Times. Instead of operating in a walled garden, Microsoft has partnered with Ubuntu to bring a Linux shell, Ubuntu, to Windows 10.

Microsoft wants users to ditch the pen and learn to love digital writing with Windows Ink. The new function will let users jot down notes, work on designs, chart things out on a map or create a reminder to call someone. Windows Ink integration with Microsoft Edge and Office means any note can be added to a calendar or promote further action such as writing a note about lunch plans that would prompt Cortana, Microsoft's digital assistant, to inquire about possible reservations.

Cortana was an important component of the Build 2016 keynote. The digital assistant will be incorporated across Windows 10 to help users better organize their lives and conversations. Cortana, available across all Windows, iOS and Android devices, can complete a text used context clues from previous or related conversations. Microsoft's digital assistant can also keep track of any meetings or commitments that can be prioritized, ignored or rescheduled.

The Windows 10 Anniversary update also transforms the Xbox One into a development kit. The update brings Cortana to Microsoft's console along with the ability to play background music in a game. With the Xbox One and PC, there's a cross-platform approach where developers can create one code for a game that can run on either system as part of the Universal Windows Platform. The update opens up a Xbox Dev Mode option for users to create apps.

The $3,000 Hololens Development Edition has now started shipping, project leader Alex Kipman and co-creator Kudo Tsunoda revealed at Build 2016. Microsoft continued to tout its commercial uses with a list of partners that include NASA, Audi, Saab, Japan Airlines and Loews. To show off its potential, there was a human anatomy demo at Build 2016 with Pamela Davis, dean of Case Western Reserve University School of Medicine. The Hololens can be used to better understand the complex human nervous system or see how a brain tumor could impact different bodily functions. 

Microsoft's plans for a chatbot army were revealed earlier Wednesday, but Nadella further elaborated on Microsoft's AI plans. When Nadella said AI should bring out the "best of humanity, not the worst," there were many chuckles from the audience due to the recent failure of its social chatbot “Tay,” which had to be deactivated after it went on a racist Twitter tirade. Nadella noted the failure, but also the success of chatbots launched in China and Japan.

An interesting omission was Windows Mobile. Wednesday's keynote did not discuss Microsoft's failure or future with smartphones or tablets, which remain unknown.