Product viral growth mechanism design

Engineer viral growth loops into product experience. Viral loop components: 1. Motivation: why users share (social currency, utility, reciprocity). 2. Ability: how easy it is to share (reduce friction). 3. Trigger: when/where sharing prompts appear. 4. Value for recipient: benefit for person receiving invitation. Viral mechanisms: 1. Referral programs: incentives for successful referrals. 2. Collaborative features: shared workspaces, team projects. 3. Content sharing: user-generated content with product branding. 4. Social proof: public profiles, achievements, leaderboards. 5. Network effects: product gets better with more users. Measurement: 1. Viral coefficient (K): average invitations per user × conversion rate. 2. Viral cycle time: time from invitation to new user activation. 3. Organic vs. paid acquisition mix. Design considerations: 1. Natural sharing moments: after positive experiences. 2. Value clarity: recipient understands benefit immediately. 3. Friction reduction: minimal steps to invite. Examples: Dropbox storage bonuses, Slack workspace invitations, Notion page sharing.