Startup Idea : Visual share of interests

Would you like to know people arround you, who are interested in the same thing as you are? You`ll choose in your smartphone app 4-5 professional and 4-5 personal interests. You can see on the map users, who have chosen the same interests as you, and you can send them a message. Usage: Example1: You are on holiday and you would like to go diving. But the boat leaves port only if 5 passengers are registered. On the beach are hundreds of people, so now you can really sipmply contact them. Example2: Students at the university would like to share their interests. If they don`t have unique network, it is really hard to find somebody who is interested in e.g. Java programming. So now you can find out that somebody is sitting fast beside. Good chance also for personnel clerk. Business plan: As you`ll finish your searching, you`ll see adds similar to your interests. E.g. for diving equipment, job offers, etc. Execution: Starting at the universities as some kind of networking, or as the open source PR of some companies.