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Very strong offshore wind (over about 35 km/h) can also spoil a wave: it can hold it up so much that it does not break, and it throws spray that blinds you. Light offshore is the dream; a light wind of any kind (under about 8 km/h) is still good, and the sea is glassy.
Wind has a daily rhythm. At dawn the land is cool and the air is still or lightly offshore. As the land heats during the morning, a sea breeze sets in from the water and the surface goes onshore. That is why "go early" is the oldest advice in surfing.
The tide changes the depth over the bar or the reef, so it changes where and how the waves break.
Drawing: The same sandbar at three tides. Low: the wave jacks up and can close out on the bar. Mid: it peels. High: it breaks near the beach and loses shape.
Which tide works is different at every spot, and at some it matters more than the swell. At a spot where rocks sit under the surface, too low a tide can make the wave unsurfable and dangerous. The app's guides say which tide a spot likes, and a plan with a chosen spot rates the hours by how well the tide fits.
Around new and full moon the tide range is biggest (springs): more water moves, currents are stronger and tide-sensitive spots are more extreme. Around the quarter moons (neaps) the range is small and the tide changes little.
In the app: The tide in the app is shown as how far from the bottom of the day it is, for example "mid tide, 0.6 m from the bottom (57%), falling". 0 % is the day's low and 100 % the day's high, so it reads the same on a big or a small tide.