Reading/Web/Projects/Improve in-article language switching on mobile web

The problem
This is intended to improve the reading experience of users who speak more than 1 language, primarily for those users whose primary language has limited content. It is quite common for such a user to want to see if the article in another language has more content or is more understandable.

Success criteria
Increase interaction with language switching by 5% on mobile web.

Join the conversation
This task is being tracked on Phabricator and we'd love to hear your thoughts.

Metrics analysis
Refer to the following for some pre-implementation analysis.

T125127 [Release] Confirm language overlay sampling on production working as expected

On 12-February-2016 before changes to the language switcher modal or introduction of a new button placement, the data on the stable channel suggested that globally the "Read in another language" button was tapped about 1.3% of the time when there was an impression of it. This was heavily influenced by enwiki traffic, where the preponderance of traffic existed at the time. A few examples where the button impression sample size exceeded the magical 30 number: On arwiki tapthrough was about 2.5%, hewiki it was about 3.1%, jawiki 0.5%, and eswiki about 0.8%. This was based on the following queries.