During my previous studies I was introduced to ancient Greek and, among other things, I learned that we believe double gamma γγ was pronounced like a prenasalised gamma, something like "ng", which certainly would explain why γγ was tranliterated and reached modern day languages as ng.
I've recently started to learn Modern Greek and my handbook, as well as Wikipedia's article on Modern Greek phonology, state that γγ is still prenasalised. However, I was surprised to see that my Greek girlfriend Evangelia pronounces her name something like "Evagelía" rather than "Evangelía" and, moreover, in a recent trip to Greece, specifically to Athens, Patras and Thira, I was surprised to see that everyone was dropping this nasalisation---or at least it was unperceivable to me---. I even asked her explicitly whether she has the impression of nasalising γγ and she told me she does not, and she added she doesn't have the impression other Greek people do in Peloponnese or Athens. Actually, I even asked random local people to pronounce "Αγγλία" and it always turned out as "Aglía".
How do we explain this apparent contradiction between academic phonology and---still apparent---spoken Modern Greek. Was this lack of nasalitation due to a dialectal variant of Modern Greek, proper to the regions I've been in?