The first day we (my adult daughter and I) tried to catch a bus at Times Square to do the South loop. We were the last in line and were not able to board. We waited for the next bus. Several people left the bus and as we started to board, a group of 6-8 people that had just left the bus pushed their way ahead of those of us in line and said "we changed our mind" and reboarded the bus, bringing with them a large group of friends that had been at the end of the line. The driver was ok with it. When we finally boarded there were only lower level seats available. It was stifling with no ventiliation. Then it started to rain and the "line crashers" all came downstairs to get out of the rain. With people in the aisles it was horrible and we just got off at the next stop. We waited until after the rain and boarded another bus and enjoyed the rest of the day.
On the second day we decided we wanted to do the Upper Loop but it required purchase of the full ticket again which was fine. Using the app, we located the stop for the Upper Loop. When we got there, the Big Bus employee said that it had been moved but the app had not been updated. We walked a few more blocks to the new stop. There were enough people that based on the number able to get on the first bus that stopped, the estimated wait time to board a bus was at least 2 hours, probably 3. We took a cab to Central Park, spent time in the north area and took a cab back to Times Square. The total cab fare was still much less than the cost of the bus that we never boarded.