We recently released a new app in the app store and are checking the sales & trends. We are not sure what the transaction type "update" actually means.
a) People who updated the app -> which means they downloaded and installed it through the update process.
b) Scheduled updated -> they see that there is an update but did not download it.
Many thanks!
Updates are pretty obvious just "updates", as everything else would be impressions, which only show up in app analytics. "Transaction type" implies that something actually happened whereas your thoughts on "Scheduled updates" are about thing maybe happening in the future.
What are units in the downloaded reports? Units can include Paid or Free downloads, Updates, Refunds, and Redownloads. These metrics are distinguished by the Product Type Identifier column. See Product Type Identifier definitions.
Source: https://itunespartner.apple.com/en/apps/faq/Sales%20and%20Trends_Reports