Bring a pot of water to a rolling boil over medium-high heat. Add the shrimp and cook for 2-3 minutes until pink and opaque. Drain and chop into bite-sized pieces.

In a large mixing bowl, combine the chopped shrimp, lime juice, red onion, jalapeño, and cilantro. Stir well until evenly coated.

Cover the bowl with plastic wrap and set aside at room temperature for 15 minutes to marinate.

Gently fold in the diced mango and avocado, combining carefully to avoid mashing them.

Sprinkle salt into the mixture and stir gently to distribute. Adjust to taste.

Transfer to serving bowls or glasses. Serve immediately or chill for up to a couple of hours. Garnish with extra cilantro and lime wedges if desired.