On different incarnations of Wikipedia the interlanguage links look and behave quite differently. Assuming that the main purpose of interlanguage links is to help people find content in their language, it is useful to see what designs behave the best and get more people to click or tap on them.
The platforms to check are:
* MobileFrontend
* iOS app
* Android app
* desktop
** On desktop it may be useful to note whether the Compact links beta feature was in use, and if it was, whether the clicked link was in the initial list or in the ULS panel.
For some non-numeric discussion of the issues see https://www.mediawiki.org/wiki/Interlanguage_links/Implementation_comparison .
(This is probably mostly work for Analytics, but I'm also tagging Mobile and Language teams, because it's closely related.)