This is the new sportting terrace, next to heliport in Rumlang, in the west side of the Kloten airport. This place is also next to the famous "Heligrill". It's very good location for spotting during the afternoon until sunset. The coordinate in Google maps: 47.452607, 8.548061.
This is the famous spotting location in Oberglatt. The best time for spotting here is during the second half of the day. One can see here many aircrafts, one by one, on final approach to runway 14. The coordinate in Google maps: 47.484275, 8.536947.