Fruit trees on road side except Jaman are a failure. Fruit trees in your house are heven for fruit flies, others are consumed in quantity that a few plants do not contribute much. I find Bananas and lemons the best utility fruit plants.
I second Sir. Arif's point of view.... nowadays many people with little knowledge of gardening and urban landscaping urge others to plant fruit trees on side walks, parks and road side... they dont realise that first of all trees do not grow by themselves in Karachi.. you must water them for 12-18 months before they could fetch their own water... fruit trees attracts so many insects and produce litter, you cannot park your car under these trees when the fruits are getting ripe..