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On the Publish page, you will manage the different versions of your application. You can think of a version as a complete snapshot of your application. You can make lots of updates to your application without making a new version, but every time you want to release those changes to a phone or other mobile advice, you will need to make proceed to the Publish page and select Make New Version.
Making a New Version
To make a new version click on the Make New Version button.
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For every build that you make a new version for, you are able to put comments. These comments are useful to track the changes you have made to your application or to denote a specific version that you might like to use. It does not matter what you put in the comments and you can change them later.
Publish an Application to a Phone
If you click on the Deploy button for an application you will see several options for deploying:
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Updating your application: Read more here: Update Application