WikiTravel Offline (Unofficial) description

How does the app work?

For non-techy users, the app works by querying Wikitravel's website, and storing the returned data locally. That's the simple explanation but it's a gross oversimplification.
There is more to it though and it's important you understand what it can do, can't do, and why. In reality the app queries the Wikitravel API, which, in non-technical terms accepts a packet of data and then sends back information based on the request. While this is in theory a lot like what you have in your browser (e.g. Chrome), actually it's rather different because the API is very far from being perfect.

In order for the app to be able to function as offline data storage the returned data has to be captured and cleansed. This also means the app needs to be able to monitor and control what you (can) do inside the app. While this might sound odd/scary it's obvious and important. There's something called WebView in Android world, which is the element of the app that shows the web contents and which you will be reading/using.
When you search for "London" (or any other place) there are 2 queries that get sent out. First a query to establish if there is a page called "London" in the language of your choice and if so what's the internal PageID and current RevisionID. At this stage the app checks if that specific combination is already stored in the local database and if so you'll see the locally stored data, if not, another query gets fired off for the actual online content and eventually the data will be presented inside the WebView (from a strictly non-technical approach, "the app".).