With the announcement that Apple will no longer provide iPhone unit sales, we wanted to flag our survey work as a potential tool to help fill the coming knowledge gap. We have been consistently tracking market share, retention rates, recent purchases, model mix, loyalty, refresh cycle length, etc (in the US, China, and other countries) for 6+ years. Comparing our upcoming measurements with historical readings will yield really helpful insight into what is actually going on with AAPL (even if they aren’t telling us quite as much going forward).
Please let us know if you would like to learn more about what we ask about in our surveys on AAPL. Just a few examples of metrics we track below (we have the raw data available in excel).