MedusApp allows beachgoers to check recent jellyfish sightings before heading into the sea, with its interactive map particularly useful along Spain’s Mediterranean coastline, including the Costa Blanca. However, it is not restricted to the Costa Blanca, or even the country. Check before you swimFor Costa Blanca residents and holidaymakers, the concept is simple. That means it is more accurate to describe MedusApp as a Spanish-developed international citizen-science project rather than simply a Costa Blanca jellyfish app. Information within the app also explains different types of jellyfish and the potential severity of their stings.