Peel avocados and cut into cubes. Do the same with the bananas. Squeeze lemon juice over the fruits to prevent discoloration. Peel and cut mangoes into cubes along with the watermelon. Mix the fruit with the chipped ice and pile into 4 individual ice cream glasses.
In a bowl, whisk together the coconut cream and simple syrup, to taste and drizzle it over the fruit-ice mixture. Serve immediately.