@Smith
Fruits contain simple sugars that require no digestion. Thus, they will not stay for a long time in the stomach. Other foods, such as foods rich in fat, protein and starch, will stay in the stomach for a longer period of time because they require more digestion. So if you eat fruit after a meal, the fruit sugar will stay for too long in the stomach and ferment. This is why people experience digestive trouble when eating fruit that way.
So, the best option is to eat fruit before any other food as it will take the curb off your appetite and make you consume less calories overall!