I assumed it was a crab apple for the last 10 years, and left it alone for the birds.. this year I decided to pick a few and try and "do something with them" but someone came to visit while they were in the kitchen and said it didn't look like crab apples she'd seen, so I cut one open and it's not an appley appearance (seeds, texture etc) at all so I didn't know..
I wondered if it might be a quince but had no idea what that would look like either hence posting for expert input
The fruit are a bit bigger than a cherry or a gooseberry, have a base that looks like the bottom of an apple, but inside is more like the texture of a gooseberry and they have turned yellow at maturity. Seeds are like nothing I've seen
Maybe I'll leave them for the birds again..