I have been able to dodge a few attacks here and there in different battles, but by and large, the most effective thing to do to win a gym fight seems to be spam tapping my screen as fast as I possibly can. Is dodging effective, and if so, how can I use it effectively (i.e. can I dodge secondary attacks which generally do more damage)?
Dodging is definitely effective but hard to do in my experience. You can dodge both the fast/normal attack as well as the special attack. Simply move to the left or right after the screen flashes yellow. It’s important to be on a good connection to get the timing right. I’m not too sure what the cue for a special attack dodge is though aside from the text bubble that shows up.
I found a useful video that shows dodging in action: