Apfel = /ˈapfəl/
Äpfel = /ˈɛpfəl/
I see what that says, but it's wrong. Look further down their page on the Umlaut itself ( http://en.wikipedia.org/wiki/%C3%84 ) and it clearly says it is pronounced as an 'E'. This is a good example of Wikipedia both contradicting itself, and being wrong. But forgetting about technology, listen to any German speak, you will hear it pronounced as an 'e'.
It won't let me reply to your last comment, as the thread is too long. So, you seem to be a native speaker of a few languages going by your levels :) - but anyway, what I will now say is, if the umlaut is pronounced 'A' still (as you say), then are you saying that the link I posted is wrong, as it says that it is pronounced 'e'. Because if you are native, ( I'm not) I know people who are, and would agree that Äpfel is pronounced Epfell, then maybe there's regional variation in Germany? I'm adamant that it is, so I'm interested to know why you say differently, if that means were both right somehow.
if the umlaut is pronounced 'A' still (as you say)
I didn't say that.
The standard pronunciation of "Äpfel" is /ˈɛpfəl/. /ˈepfəl/ is a regional variation. It's not common to pronounce the short "ä" (standard pronunciation /ɛ/) as /e/, but it is relatively common to pronounce the long "ä" (standard pronunciation: /ɛː/) as /eː/. Note that the Wiktionary page only gives an English approximation, not an exact equivalent. I'm using the IPA because it's unambiguous.
This is what /ɛ/ sounds like: http://en.wikipedia.org/wiki/Open-mid_front_unrounded_vowel
This what /e/ sounds like: http://en.wikipedia.org/wiki/Close-mid_front_unrounded_vowel