I'm a believer in the barometric pressure trends theory of fishing - at least for smallies. I'm a programmer by day, and made an app to measure the trends that I've been using all summer. I decided to share it, so it's on GooglePlay (Apple devices don't have barometers) for anyone interested. Needs an Android phone that has a Barometric Pressure Sensor in it.
I have tried fishing by moon phases, wind speed and water temp, and barometric pressure for me seems to work pretty good. But I mostly fish smallmouth between Ottawa and Peterborough.
https://play.google.com/store/apps/details?id=com.garret.fishingbarometer