Select "doesn't need to be translated" in translations
Many of the documents have titles that are just names, or something that doesn't need to be translated, so it would be nice if you could just click on a button that says "This sentence doesn't require a translation."
I'll add another suggestion to this: If the translation is the same as the source, Duolingo should give fewer points. It is not cool to earn points by copy-pasting.
Specifically on the iphone I sometimes wished that I could at least easily copy individual words from the original to the translation - i.e. tap on a person's name in the original to have it appended to the input - quite a number of sentences have names in them - so the sentence needs translating - but the names certainly don't...
Oh, yeah, especially with the names that have accents, or ones with Chinese symbols (yes, I have had a sentence like that and it took me 20 minutes to get the chinese characters so I could put them in my translation)