We have [[https://www.mediawiki.org/wiki/Wikimedia_Apps/Short_descriptions/Research|detailed data]] on the number of edits made via the app's new custom Wikidata description editing workflow, but per recent conversations with @Charlotte we should also know the ongoing rate of "normal" article edits made using the app (i.e. edits on Wikipedia wikis).
We can easily determine the total number of edits made via either the iOS or the Android app by using the public `mobile app edit` tag (example: [[https://en.wikipedia.org/wiki/Special:Tags | English Wikipedia]]), which already indicates that the vast majority of edits from the Android app still comes from non-description edits (cf. T184096#4164186 ). However, this does not give us the numbers for Android (or iOS) separately.
I see several possibilities here (@Neil_P._Quinn_WMF and/or @mpopov will likely have additional perspective):
# use the user agent field from the checkuser table to extract Android app edits
# rely on the `saved` events https://meta.wikimedia.org/wiki/Schema:MobileWikiAppEdit (mindful that this data will be a bit less exact due to opt-outs - which may be more frequent among high-volume contributors too, and that the method can't be used for iOS, per the talk page comments there)
# use webrequest data? (the code required for detecting the corresponding requests from the apps could probably be adapted from e.g. the queries for the [[https://wikitech.wikimedia.org/wiki/Analytics/Data_Lake/Traffic/mobile_apps_uniques |apps uniques]])
# Provide separate edit tags for the Android and iOS app going forward (this may involve work on the clients, although a first step would probably be to look at the code that currently creates the `mobile app edit` and see if it can be modified. See also. https://www.mediawiki.org/wiki/Manual:Tags )
It appears natural to calculate this number by project (wiki) first, with additional dimensions to be decided.
**Update:** It looks like we may want to go with the general solution of splitting the `mobile app edit` tag into separate tags for Android and iOS (included as #4 above), which will also enable calculation of various other relevant metrics from the public data.