So both are valid, but the most common way is 'càit'. We're changing the best translation from 'càite' to 'càit' in the next update (although both will be accepted) to bring it in line with the Gaelic Orthographic Convention. The problem with this is - both Tree 1 (the one currently released, that you are learning on) and Tree 2 (the one we are working on) are linked. So certain changes that are made to Tree 2 carry over to Tree 1, and vice versa.
This is great in some regards (eg when adding alternative translations), but not in others. It means that if we change any of spellings of the words or phrases taught in Tree 1, we have to have both the old and new spelling saved as a 'best' translation so as to avoid bugs in the incubator. At least until Tree 2 goes live anyway. That's why both answers are being marked as typos - they're both right.
I know that it's frustrating from the user end, but I can count on one hand the amount of lexeme corrections we've made between Tree 1 and Tree 2, so thankfully it's only happening with a few sentences. :)