What is a Supply-Side Platform and its Importance

Publishers often struggle to secure fair prices for their ad inventory because demand is fractured across multiple ad networks, and legacy setups can’t adjust to real-time bid shifts. This fragmentation leads to unsold impressions and under-priced slots, leaving revenue on the table and complicating yield management.

A Supply-side platform (SSP) automatically sends ad requests into real-time bidding across ad exchanges and demand-side platforms (DSPs), ensuring publishers capture the highest price.

In this blog, we’ll define SSPs, explain their core functions and benefits for publishers, and compare them with DSPs in Real-time bidding (RTB) auctions. We’ll then explore how SSPs support mobile game monetization through SDKs, header bidding, and privacy-compliant attribution. Finally, we’ll share practical steps to choose, integrate, and optimize your SSP for maximum fill rate, eCPM, and yield.

What is a Supply-Side platform (SSP)?

A supply-side platform (SSP) is a technology platform that manages a publisher’s ad impression inventory across multiple ad exchanges, automating ad inventory sales and optimization to generate revenue for publishers.

It acts as a connector between publishers and demand sources, such as ad networks, ad exchanges, and DSPs, so that available ad space can be offered to many buyers simultaneously. SSP software supports display, video, mobile, and native ad formats, offering these impressions to potential buyers through real-time bidding (RTB) auctions.

By sending each ad impression into ad exchanges, SSPs enable publishers to receive bids from DSPs and ad networks, ensuring their inventory sells at the best price.

Difference Between SSP and DSP

SSPs and DSPs are two sides of the programmatic advertising ecosystem. SSPs help publishers sell their ad inventory, while DSPs enable advertisers to buy that inventory efficiently.

To clearly understand how SSPs and DSPs differ and complement each other, here’s a side-by-side comparison:

This interaction between SSPs and DSPs forms the backbone of programmatic advertising, facilitating efficient and automated buying and selling of digital ad space.

How SSPs Work in Mobile Games

SSPs open auctions at peak moments, like right after a level ends or a reward unlocks, so buyers compete when players are most engaged. This boosts publisher revenue without disrupting gameplay. Ads load seamlessly at those critical points, keeping players immersed while maximizing yield.

1. SDK Integration & Mediation: 

Modern SSPs provide lightweight SDKs or server-to-server APIs that plug directly into common mediation layers like Google AdMob and MoPub. This setup:

• Reduces app bloat: Publishers only add a small SDK footprint.

• Speeds time-to-market: Pre-built integrations handle multiple ad networks with one codebase.

• Improves performance: Server-to-server calls cut on-device load.

Easier SDK integration means faster ad campaign launches and quicker optimization loops, helping you seize moments of high player activity to drive more installs, without delaying your release schedule.

2. Header Bidding for Games:

SSP-driven in-app header bidding is a unified auction that allows every connected DSP, ad exchange, and network to bid on each impression simultaneously rather than through sequential waterfalls. Waterfalls were the traditional method of offering inventory, one exchange at a time, in a fixed order, and remained the industry standard until header bidding gained traction around 2014.

For mobile games with high session density, this approach typically:

• Boosts eCPM: More competition drives up the winning bid.

• Increases fill rate: Even niche or rewarded-video slots get filled more often.

• Maintains UX: Modern header bidding wrappers handle bids in the background, mostly in under 100 ms, so ads load seamlessly.

3. Privacy & Attribution:

To adapt to Apple’s App Tracking Transparency, leading SSPs are now building in SKAdNetwork support and enabling IDFA-less attribution flows via their SDKs or MMP partnerships. This means:

• SKAdNetwork-first bidding: Game apps register wins and conversion values without user-level identifiers.

• IDFA-less yield management: SSPs collaborate with mobile measurement partners to use probabilistic or consented-data methods when IDFA is unavailable.

• Compliance by design: You maintain revenue without violating iOS privacy rules.

Also Read: How to Optimize UA Budget Allocation in Mobile Advertising in 2025

Key Features & Functionalities

The role of an SSP in digital advertising is multifaceted, offering a range of tools to optimize ad sales and publisher revenue. Let’s take a closer look at how these features work together to deliver results:

1. Real-Time Bidding (RTB)

Real-time bidding is the process where, in just milliseconds, an SSP auctions each ad impression among multiple buyers. When a user loads a page, the SSP sends details of the opportunity (such as audience attributes and placement size) to DSPs and ad exchanges. These buyers then submit bids, and the SSP awards the space to the top bidder before the page loads. This lightning-fast auction maximizes revenue for every single impression by ensuring the highest bidder wins.

2. Price Floors & Yield Management

Price floors are minimum bids that publishers set to avoid selling impressions too cheaply. Using dynamic floor pricing, the SSP adjusts these minimums based on demand levels, raising them during high-traffic periods and lowering them when traffic dips to protect against undervalued bids and improve overall yield. 

Yield management features go further by analyzing historical demand patterns and optimizing auction rules, such as choosing between first-price and second-price auctions, to boost average earnings per impression.

3. Frequency Capping & Ad Quality Controls

Frequency capping ensures that the same user does not see the same ad too often, preventing ad fatigue and improving user experience. SSPs work with DSPs to enforce limits on how often a single ad creative is shown to a user within a set time frame. Ad quality controls let publishers block low-quality or irrelevant ads and maintain brand safety by blacklisting specific categories or advertisers, so only suitable, high-value ads appear on their properties.

4. Granular Analytics & Reporting

SSPs offer detailed dashboards that break down key metrics, such as effective cost per mille (eCPM), fill rate (the percentage of ad requests that result in served ads), bid latency (the time it takes to receive bids), and partner performance statistics (like win rates and revenue contributions). These analytics help publishers identify underperforming partners, spot trends in ad demand, and fine-tune auction settings or floor prices based on real data.

SSPs help publishers to maximize their ad revenue by connecting them with multiple demand sources, optimizing pricing, controlling ad exposure, and providing valuable performance analytics.

Now that you’re familiar with an SSP's essential capabilities, let’s move on to the direct benefits for mobile game publishers who adopt this technology.

Benefits for Mobile Game Publishers

SSPs provide several tangible advantages for mobile game publishers, improving key revenue metrics and enhancing the user experience:

1. Higher Fill Rates via Expanded Demand Networks

An SSP opens your ad inventory to dozens of demand sources, ad exchanges, DSPs, and ad networks, rather than relying on a single partner. This broad exposure dramatically shrinks unsold impressions and boosts your overall fill rate (the percentage of ad requests that result in a served ad). 

For mobile games, higher fill rates translate directly into fewer missed revenue opportunities and steadier cash flow from in-game ads.

2. Improved eCPM & ARPU 

By running each impression through a real-time auction, an SSP drives competition among buyers, which lifts the eCPM (effective cost per mille), the average revenue earned per thousand impressions. Additionally, publishers can set price floors to prevent impressions from selling below a minimum CPM, ensuring the fair valuation of their most valuable placements. 

Higher eCPMs boost ARPU (average revenue per user), since each active player encounters higher-valued ads without compromising ad load.

3. Automated Auctions and Unified Dashboards

Legacy methods required manual negotiations and direct insertion orders for each campaign. An SSP automates this entire workflow, running auctions, enforcing floor prices, and consolidating reporting, through a single SDK integration and dashboard. 

This automation reduces administrative overhead, allowing you to focus on creative and strategic optimizations and ensuring a faster time to market for new ad partners.

4. Relevancy Targeting Minimizes Intrusive Ads

Modern SSPs offer frequency capping and ad fatigue controls that prevent the same ad from overserving players, reducing the risk of annoyance or churn. Through detailed audience segmentation based on user behavior and identifiers, SSPs ensure each ad matches player interests, maintaining immersion and session length. 

Now that we've covered how SSPs enhance revenue, fill rates, and user experience, let’s walk through how you can bring these benefits to your game with a step-by-step SSP integration process.

Actionable SSP Integration Steps

With the proper implementation, publishers can unlock new revenue streams and optimize ad delivery at scale. Here's how to get started:

Step 1: Select & Evaluate SSP Partners 

When choosing an SSP partner, focus on comparing their SDK sizes to keep your game bundle lean and startup times fast. Smaller SDKs help your game load quicker, improving user experience. Also, measure bid-response latency by subtracting network latency from each SSP’s max auction time. You want this to stay under 70 ms to avoid auction timeouts that can hurt your UA performance.

Confirm that partners connect to Tier 1 markets and top DSPs in your target regions to ensure global demand coverage. Lastly, identify each SSP’s specific minimum traffic criteria rather than assuming 100K; for high-tier SSPs, you may need 1M–10M monthly impressions to prevent rejection or low auction priority.

Distinguish between SSP (inventory holder) and mediation (aggregator). Based on these criteria, a shortlist often includes PubScale, AppLovin, Smaato, and AdColony. 

Key action: Create a comparison matrix (SDK size, latency, reach, traffic minimum) and rank each candidate to focus on the top 3–4 SSPs. SDK size is one factor, but you must also assess CPU usage, memory footprint, and dependency conflicts, all of which influence load times and stability.

Step 2: Integrate the SSP SDK (or mediation)

Use the SSP’s SDK to connect your game to the platform. Follow the SSP’s integration guide and add their SDK library to your game project. If you work with multiple ad networks, use an ad mediation solution (which acts like an SSP) so all partners run through one SDK. Proper SDK integration ensures ad calls go out correctly and that the SSP can manage auctions for your ad placements.

Key actions: Initialize the SDK in your app code and register each ad placement. Test basic ad requests (e.g., test ads) to confirm the SDK is working.

Step 3: Configure pricing and delivery settings

Use the SSP dashboard to set pricing rules and delivery controls. Set a price floor (minimum bid) for each ad placement so impressions aren’t sold for too little. Price floors protect your revenue and ensure you’re paid fairly for each impression. 

Also set frequency caps to limit how often the same user sees a given ad (avoiding ad fatigue). Configure ad formats (interstitial, rewarded, banner) and any targeting or brand-safety filters the SSP provides.

Key actions: Begin with mid-range floor and cap settings to avoid over- or underpricing your inventory. Set price floors based on historical average eCPMs rather than assuming steady increases, since eCPMs often fluctuate quarter-to-quarter and year-over-year across formats. 

Step 4: Test and measure performance

Run test campaigns or use the SSP’s test tools to measure results: 

• Track fill rate (the percentage of ad requests that return an ad). A higher fill rate means better inventory utilization. 

• Monitor latency: Real-time auctions happen in milliseconds, so verify ad loads are fast. If ads take too long (high latency), it can hurt user experience. 

• Measure CPM/eCPM (cost per mille) to see what you earn per 1,000 impressions. Compare these to expectations or benchmarks.

• Define test variants: Compare different SSP combinations, floor levels, and bidding models (header bidding vs. waterfall) to quantify incremental lift in fill rate and eCPM.

• Deploy statistically: Run tests over a complete UA cycle (typically 7–14 days) to capture both early and late retention impacts, then select the configuration with the highest overall ROAS.

Key actions: Check that the SSP is filling most requests. Logging or MMP analytics should be used to record response times. The auction and delivery should happen within a few hundred milliseconds. Note your average CPM and adjust the floors if they are far below the target.

Step 5: Optimize by adding demand and iterating

Increase competition to boost yield. Add more ad demand sources or enable header bidding (in-app bidding) so multiple SSPs bid simultaneously. By design, an SSP connects to many exchanges and networks, so engaging all available sources can raise your fill rate and average CPM. 

Review the data regularly and tweak settings. Increase price floors if fill is too high or lower them if fill is low. Adjust frequency caps based on player feedback (e.g., raise the cap if revenue is low, drop it if players see repeats).

Key actions: Enable header bidding or connect additional SSPs/networks to run auctions together. Continuously A/B test different floor and cap settings. Monitor that revenue (eCPM) improves as competition increases.

Conclusion

Supply-side platforms (SSPs) have revolutionized the mobile gaming ad industry by automating real-time bidding, dynamic price floors, and yield management. By integrating lightweight SDKs or server-to-server APIs into mediation layers, SSPs streamline ad operations, reduce latency, and boost fill rates, ensuring every impression competes in a unified auction. Advanced features such as header bidding, frequency capping, and SKAdNetwork-enabled attribution allow publishers to maximize eCPM, protect user experience, and stay compliant with evolving privacy standards.

An effective SSP strategy ultimately drives higher ARPU and consistent revenue streams and frees your UA teams to focus on creative and strategic optimizations rather than manual setups and negotiations.

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FAQs

1. What’s the difference between header bidding and waterfall?

In waterfall (sequential), each network bids one after another, often leaving revenue on the table. Header bidding runs all bids simultaneously, driving up competition and eCPM in under 100 ms.

2. How do price floors improve yield?

Price floors set a minimum bid threshold. Dynamic floors adapt to traffic peaks and valleys, preventing undervalued sales and increasing average earnings per impression.

3. Can SSPs work without SDKs?

Yes, many SSPs offer server-to-server integrations. These reduce app bloat and latency by offloading auction logic off the device, while still feeding mediation layers like AdMob or MoPub.

4. How do SSPs handle iOS privacy changes?

Leading SSPs integrate SKAdNetwork for attribution and partner with MMPs for probabilistic or consent-based IDFA-less flows, ensuring compliant bidding and conversion tracking.

5. What metrics should I monitor post-integration?

Focus on fill rate (served vs. requested), eCPM/CPM to gauge pricing, bid latency for UX impact, and partner win rates. Using these, you can fine-tune floors, caps, and demand sources.