There must always be changing user acquisition strategies for B2C startups and they must grow and develop constantly. Social media marketing,search engine marketing,SEO and all the other normal stuff from the book has never been the driver of growth.
Growth hacking strategies for startups are a lot.They come up everyday and you must ride the wave. however,there are some experimented ways that have provided results for different types of businesses and startups.
Here is a detailed infographic that will guide you which channels to use for B2C user acquisition.
Infographic Source: http://www.marketingmasala.com/customer-acquisition-strategy-b2c-startup/