What is Ad Mediation?
Ad mediation is a technology solution that allows app publishers to manage multiple ad networks through a single SDK integration. The mediation platform automatically selects which ad network serves each impression to maximize revenue and fill rate.
Instead of integrating 10+ individual ad network SDKs, publishers use one mediation SDK that handles the complexity of working with multiple demand sources.
How Mediation Works
Waterfall Model
Traditional mediation uses a "waterfall" where ad networks are called in sequence based on historical eCPM:
- Ad request sent to highest-paying network first
- If no fill, request moves to second network
- Process continues down the chain until ad fills
- eCPM floors prevent low-value ads
In-App Bidding (Parallel)
Modern mediation uses real-time bidding where all networks compete simultaneously:
- Ad request sent to all networks at once
- Networks submit real-time bids
- Highest bidder wins the impression
- True price discovery maximizes revenue
Top Mediation Platforms
| Platform | Bidding | Key Strength |
|---|---|---|
| AppLovin MAX | Yes | Gaming focus, strong bidders |
| ironSource LevelPlay | Yes | Gaming, cross-promo |
| Google AdMob | Yes | Scale, Google demand |
| Unity LevelPlay | Yes | Unity engine integration |
| Fyber | Yes | Transparency, bidding |
| Chartboost | Yes | Gaming, cross-promo |
Benefits of Mediation
- Higher Revenue: Competition between networks drives up eCPM
- Better Fill Rate: Multiple fallback options ensure ads always show
- Simpler Integration: One SDK instead of many
- A/B Testing: Easy to test new networks and configurations
- Unified Reporting: Single dashboard for all ad performance
- Reduced Latency: Optimized ad loading improves UX
Pro Tip: Hybrid Approach
Use in-app bidding for demand that supports it, with a traditional waterfall as fallback for non-bidding networks. This "hybrid" setup captures the best of both models.
Mediation Best Practices
- Integrate 5-10 Networks: Enough competition without SDK bloat
- Enable Bidding: Switch networks to bidding when available
- Set Smart Floors: Use floors to prevent race-to-bottom pricing
- Monitor ARPDAU: Track revenue per daily active user, not just eCPM
- Test Placements: Different mediation configs for different ad placements
Waterfall vs Bidding Comparison
| Aspect | Waterfall | In-App Bidding |
|---|---|---|
| Price Discovery | Historical averages | Real-time market price |
| Setup Complexity | Manual optimization | Automated |
| Latency | Higher (sequential) | Lower (parallel) |
| Revenue Potential | Good | Better (+10-30%) |
| Network Support | All networks | Major networks only |