The application «RoomsInSifnos» is one application with all the necessary information to a user-traveler about Sifnos. The user can through this application to looking for accommodation and find everything: hotels, café, various areas of the island. Can be informed about different activities that may take place on the island during his stay. Also can be informed about the natural beauty of Sifnos by various Video. It has the ability to share via Facebook and Twitter photos and texts that sees through the APPLICATION. This application contains a complete and modern mechanism for searching in rooms, studios, apartments, houses and villas by area on Sifnos island. The user-traveler has the ability to choose through filters, the type of benefits/facilities he wants for his stay (WIFI, Parking, Breakfast, Jacuzzi, Pool, Offers), but especially during the summer season can be informed about the availability of accommodation on the island! The traveler can navigate with maps of the island and choose the language in which he wants to install the application (Greek, English and French). The application is linked online to the web site of the island, so all the information is automatically updated, so each user-visitor always has at his disposal updated content. But at the same time is an advertising effort of Sifnos with beautiful pictures, texts and videos through MOBILE STORES market.