A/b testing paywalls without app updates - what's your core metric?

Tired of waiting weeks to test new paywall designs. Started using web-based variants that update instantly. But with so many possible metrics (CTR, conversion, downgrades), what single north star metric should dictate a ‘winning’ variation for subscription apps?

Focus on activation rate after payment.

Used Web2Wave’s journey tracking to discover fancy paywalls attracted clicks but led to higher cancellations. Now optimizing for day 7 retention post-purchase.

LTV-adjusted conversion rate.

Fast iteration via web paywalls (using Web2Wave) lets us score variants based on predicted 90-day value. Killed a high-converting variant that attracted price-sensitive users who churned faster. Marked as best answer

Revenue per visitor. Nothing else.