It seems that they dont have a lot of data yet to give any sort of useful prediction outside the next couple of months. Nothing that Google Flights doesnt already do. I cant get a prediction for flights in May nor can I sign up for a notifications for prices at that time. I dont see the point. Its also not intuitive, it set the region and currency to Chile and it wasnt easy to find where to change the currency to CAD (I mean come on, I installed it from the Canadian App Store...)
TrackTer Girl about Hopper: Flights, Hotels & Cars, v3.0.0