This article is an explanation of how to do over the air deployment of an ad hoc iOS application build manually using a self-hosted web server. If self-hosting of the ad hoc files is not a requirement then I would recommend using a third party service such as Test Flight or a possibly a self hosted, fully managed solution like Hockey.
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Edit: For iOS 7.1 onwards make sure you are using https url for plist file link.
itms-services://?action=download-manifest&url=https://example.com/Application.plist
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