Recommendation for CEO:

• Discontinue or reduce:
  - Online Radio: highest CPA, lowest return → allocate budget immediately
  - Bing CPC: poor performance across all attribution models
  - Podcast: cost not proportional to acquisition
• Maintain and optimise:
  - Apple Store: consistently lowest CPA across all three models → strongest performer
  - LinkedIn: strong first-click and multi-touch → good for awareness and conversion
  - Banner Ads: solid across all models
• Invest more in:
  - Google Adwords: mid-range CPA but high volume potential with increased budget
  - Twitter: strong last-click performance → good conversion closer, worth testing with higher spend

KEY INSIGHT:
Apple Store performs best regardless of attribution model → this is the most reliable channel.