Is is possible to use the 3.5 jack on the Raspberry Pi as a line-in?
I need to record audio through the Pi and I didn't find anything conclusive about its audio capabilities. Would like to make sure before searching for a sound card.
You cannot record sound through the 3.5 jack of the Pi right now. See here http://www.raspberrypi.org/help/faqs/#audioStandard
As an alternative you can use a sound card like the Wolfson or a USB microphone/sound card. If you go with the Wolfson (which is the option I went with) there are two important things to know before you buy:
Even given all the above, the Wolfson works pretty well for my purposes. If you already have a Pi, I would recommend the Wolfson if you have an A or a B, and a USB card/mic if you have a B+. If you don't have one, you're probably better off sticking with a USB option for now, since it will be extra work locating a deprecated Pi for no real benefit.