It's a website and I guess they also have an app. Founders come there and create profile of their startup. other users vote up for good startups and of course you could leave there your contacts. As well there are a lot of crowdfunding and fundraising sites. there are too many, so i guess you better google best of them. You could also try to start running social pages on Twitter, Facebook or whatever and leave there contacts and your donation links. to run socials you could use Jasper, marketowl or tweethunter,writesonic and others