Hi all!
So, Karsten, Nicolas and I were sitting together for a while and were looking at past data for figuring out how many users downloaded and updated their Tor Browser over time.
We actually got more questions than we were able to answer but I guess that's fine for a start.
Here are the graphs showing initial downloads, update pings and update requests over time:
https://people.torproject.org/~karsten/volatile/torbrowser-annotated-2016-09...
We annotated the grapgs a bit highlighting things we wanted people to point to.
The initial downloads are the number of package downloads from the website for all supported platforms (Windows, OS X and Linux). Apart from spike (5) all events seem to be non-Tor Browser related.
* On the downloads graph we seem to have a spike (5) in new downloads with the release of Tor Browser 6.0. Maybe because it was much more widely publicized in the media than previous/later releases?
* On the same graph, a big spike (6) can be seen at the same day the new board got announced.
* There are other spikes on the initial downloads graph (1, 3, 4) where we have no idea what happened while (2) is probably just an outlier.
The update pings are made by Tor Browser instances roughly twice a day and they indicate the number of active Tor Browser users. More importantly, one can see the decrease or increase of Tor Browser usage over time.
* As (2) in the downloads graph (7) seems to be an outlier as well.
* We don't know what (8) or (9) is but it seems to us we are losing users over time and are only getting them back slowly if at all. A weekday/weekend pattern is visible there as well.
The graph with the update requests is basically showing how fast users are updating to newly released Tor Browser versions.
* (10) shows a large spike correlating to the 6.0 release. It is not clear to us where all those update requests were coming from given the update request pattern before/after 6.0. One plausible explanation could be that our infrastructure was heavily overloaded causing clients to retry fetching the update.
We'd love to hear feedback, especially those that could shed light on the events we did not have an explanation for.
Georg