Topic on Extension talk:MobileFrontend

I  have setup a Mediawiki family and installed the Mediawiki Mobilefrontend Extension for better mobile usability.

The extension documentation says that it is used on Wikimedia projects (like Wikipedia).

The extension gives the same look as what Wikipdia looks like on mobile, however, I noticed a big difference.

The Wikipedia on mobile seems to go to a mobile subdomain, in addition to the format that the Moileforntend Extension provides.

for example, a page about the "World Cup" has this url when viewed on a desktop computer:https://en.wikipedia.org/wiki/World_Cup

while it has this url when viewed from a mobile phone: https://en.m.wikipedia.org/wiki/World_Cup

My questions are:

1- Is this really a redirection to a mobile subdomain? or a mirror installation?

2- What are the benefits of redirecting to a subdomain while the Mobiefrontend extension provides the formatting already.

3- How does the data gets synchronized between the main site and the mobile site?

1. Same installation.
2. Can you elaborate?
3. Both the main site and the mobile site use the same backend, the presentation is just different.

The main benefit is caching.

If you are using any kind of caching for your HTML you may find it easier to do that on a separate subdomain rather than serve different experiences on the same domain.

wgMobileUrlTemplate is how you do that.