Canistel

U r right Daehler, from ur suggested botanical name i got the common name 'canistel'
I remember it was the name tagged on the tree
thank u so much..

I'm guessing this might be an egg fruit (Pouteria campechiana) that hasn't gotten the tropical climate it needs to fully ripen. In that case, inside you should find a large black seed and pasty flesh the texture of cooked egg yolks (when ripe).
The fruit shape varies from elongate to nearly round with a dimple at the end.
http://www.botany.hawaii.edu/faculty/car...
http://www.fruitlovers.com/Eggfruit3Type...

Looks like a type of mango.