Office Presentation Service
You can use PowerPoint's Office Presentation Service to share your slide shows in real time online.
Go to the Slide Show tab and select Present Online . . . Office Presentation Service.
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. . . you will be prompted with this message and can share your PowerPoint if you have a Hotmail account:
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A web link will be created that you can share with others
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Other people can even view your presentation in real time on their smart phone. My test PowerPoint worked fine when I put the link in the Chrome App on my iPhone 6. There was about a 5 second delay between slides advancing on my laptop and appearing on the phone.
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You leave the current slide up for your audience, perform edits and then resume.
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