Lightly toast tortillas in a nonstick skillet or oven and transfer to serving plate. Spread mozzarella in the middle of each tortilla.
Beat eggs in a small bowl. Heat olive oil in the same skillet over medium heat. Add egg and stir until egg is just cooked through. Divide the egg into four portions and immediately transfer to the top of each tortilla, letting the heat of the egg melt the cheese.
Top tortillas with tomato, avocado and shrimp. Drizzle lime juice on top. Season with salt and pepper.