I find the seeds of apples and oranges and pears to be usually very soft and easy to crunch. I just munch on them while I eat the rest of the fruit. it's a fruit, God made man to eat fruit from a tree, I figure he put the seeds in there for my health.
We commonly eat banana seeds, a few green/yellow/red pepper seeds (though those are usually swallowed instead of chewed), almonds, cashews, brazil nuts, hazel nuts, walnuts, pecans, pistachios, macadamias, filberts. However, not every tree seed is good for you apparently. some tree seeds I am told are poisonous. I usually stick with the ones I buy at the store. peanut & Almond butter mmm.
The seeds from fruit contain Vitamin B17 which is sorely lacking in our diet.
I don't think you would get the benefit from the seed unless you chew it.