I answered "the spider has the sugar" first and got it wrong, and the answer box said "the spider has got sugar". The second time i answered i said " the spider has got sugar" and it said it was correct, but is instead "the spider has sugar" - but i thought 'ag an' means 'has the'?
Not quite; Irish has no verb for 'to have'. Instead of "[Person] has [thing]", you say "[Thing] is at [person]". "Tá" means "is" -- remember that the verb comes first in Irish -- and "ag an" actually means "at the". So the literal meaning of the sentence is "Sugar is at the spider." Of course, we'd never translate it that way in English, but it shows how the word "the" is attached to the spider instead of the sugar. Does that make sense?
You're far more likely to get an answer to a general question about Duolingo functionality in either the general Duolingo topic or the Troubleshooting topic, rather than tucked in to one of about 20,000 sentence discussion threads.
And there is more than one "app" - the app available on iPhones is not the same as the app available on Android devices, and that's not the same as the app that is available on Windows devices, and none of them are the same as the web based Duolingo.