I personally think after, Because breakfast is a meal and fruits are a dessert, breakfast comes before dessert so after breakfast we should have fruits.
Before breakfast so that the fruits won't have to stay in our body waiting to be processed for so long that it creates toxins.
you can eat before or after! if you want to feel energised, eat juicy fruits before with a high water rate so you feel refreshed. you could eat fruits /with/ your breakfast, sprinkle em on yoghurt or slice bananas on toast! its totally up to you:)
It depends if your not a huge breakfast eater, workout in the morning, and need a little fuel for the workout; eating fruit like a banana or apple can be beneficial in this instance. However, if breakfast is primary to you, you should have fruit after; with this you could gauge how full you are and might want to save the fruit for a snack later.
Before so the fruit can have time too take effect and you can really see if the fruits will fill you or not. Then you can judge weather you wanna add more to the plate or not.
I don't have a lot knowledge about the topic but fruits blend well into the breakfast. If you eat fruit before breakfast it will probably make you feel full so you won't eat enough food. If you are trying to lose weight it is a good thing actually but it doesn't suit me, I'm slim. Eating fruit after breakfast won't cause any problem- it is a better option than jams.