Indeed the documentation for deployment to webapps
states that it is possible to use version of Azure SDK later than version 2.6.
You must have installed Azure SDK 2.6 or later or Visual Studio 2013 Update 2 or later.
There must be no problems using a version of Azure SDK larger than 2.6 tough I have to point out at the time of releasing the support for Azure web apps the tested case was using Azure SDK 2.6, we are not ware of any issues with using an upper version of the SDK.
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