As david wrote, the new UI implementation is a work in progress towards a future stable version in which the new UI will become the default.
When this process is completed, we'll retire old templates and create new ones (e.g. "Mobile Application" for mobile only, or "Mixed Application" for an application woth both desktop and mobile screens).
Currently, read "New Mobile Application" as "application template with support of new UI, also for mobile".
Anyway, there no no "mobile widgets", just Display ones.
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