Only the thermal shift will help you pinpoint and confirm ovulation with any kind of certainty, while all other signs are good indicators that ovulation might be approaching and that you have increased fertility. While it is certainly possible to ovulate without your temperature showing it, (especially if your temperature-taking habits are less than ideal), ovulation can only be pinpointed by a thermal shift.
This is because progesterone, the hormone that is released only after ovulation, causes your temperature to shift slightly- so once you have a thermal shift, you can be reasonably sure that you ovulated on the previous day. Once you have a sustained thermal shift, Fertility Friend will confirm ovulation for you and draw crosshairs on your chart. You should keep having intercourse until ovulation is confirmed by a clear and sustained thermal shift.