The Foundation has been working on building in support for ZIM files to the Android App for Wikipedia. We're been in touch with Emmanuel quite a bit about how this might work.

We've taken on some user research in 2 forms to support this work. 

1. An online usability study using usertesting.com

2. An on the ground study in Pune, India 

You can see the results from both studies here (linked in "Research findings"): https://www.mediawiki.org/wiki/Wikimedia_Apps/Offline_support/V1_User_research

The biggest takeaways that I think will be interesting to you folks are around size and topic of content. Respondents are largely uninterested in large file sizes (over 100MB) and would prefer that these files be very topic specific. These are people working from their own Android phones, who have connectivity at least some of the time.

Let me know if you have any questions.

Anne

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