This page contains random info on Apple's 'new' language,
Swift.
Thre are several email newsletters that provide updates on
Swift (which is rapidly evolving) and reviews of papers,
conferences, useful pods etc.
Pods are modules that are published by the developer community,
and which you download and link with your app. You specify the
pods that you want in the podfile file in the main
directory of your app file system. Use the command pod init
to download the initial code, and pod update to download
any updates.
There are plenty of review sites online (e.g. here), but these are
the ones that I have found most useful in my apps: