An ICO ( Initial Currency Offering ) is a type of funding using cryptocurrencies. Mostly the online funding process is done by crowdfunding. Yes sure, You can use the social media website to promote your services. Here you can promote your service online with multiple social websites. You can promote it Facebook, Instagram, twitter and google plus. Instagram & Twitter make your online promotion to different to other social media because it used hashtags to attract people whose interest in it.
Telegram, Twitter, reddit, BitcoinTalk, discord etc have played vital role in the promotion of ICO. Of course, you need social media to spread the news to alert investors.