The Different types of Viral Loops

• Word of mouth
• Organic: a user invites another through natural, non-incentivized, usage. (e.g., when setting up a project in Airtable, when setting up their LinkedIn profile)
• Casual contact: as a user uses the product they naturally, but indirectly, expose it to non-users. (e.g., someone responding to a SurveyMonkey survey signs up to be a user, embedded chatbot with branding gets someone to sign up for that product)
• Incentivized: “every x friends, you get y” — align the incentive with the value prop of the product for that type of user (e.g., zynga focuses on fun, dropbox on storage, wealthfront on money). Find the incentive that also helps build the right habit - e.g., for postmates the incentive is a credit that gets the user to order more themselves in a short period of time.

Examples:

• Dropbox: casual contact (sharing files) and incentivized (referral program)
• Uber: all of them - WOM as people share rides, incentivized via Uber credits, casual contact via “Share ETA” feature, organic “Split fare”

Ceiling/Saturation for Virality — for an individual user, what percentage of their network is viable to invite? (Total network → target for product → Not using product)

• k factor
  • i = number of invites sent out to each new customer
  • c = % of invites that convert to customers
  • k = i * c

Look at k factor for a cohort - can take many different shapes.

Example:

• Dropbox: new user signs up, shares file, notification is sent, user responds, new user.
  • K factor goes up on a per user basis over time, shape of the curve will change based on the type of viral loop — if it’s incentivized for a reward the k factor may spike and then drastically flatten after that.