I'm learning Russian, thanks to an iPad app. Something I always wanted to do.
If you want to translate when you're on Skype, you could open Safari and set it to Google Translate. Now that there is the four finger swipe, it is really quickly to copy, swipe to safari, paste and translate, no? It is not perfect, but a fairly okay workaround.
I think people forget that Microsoft make Windows, but most of the stuff we use there is an add on from a third party developer, such as Google, Yahoo, Scrivener etc. in that way, Apple is no different, but because it is new to us, we just have to give it a little more thought.