How Postbacks Work
A postback is a server-to-server HTTP callback that transmits conversion data between systems in the mobile advertising ecosystem. When a measurable event occurs, an app install, a purchase, a registration, the attribution provider sends an HTTP request to a predefined URL on the ad network's server, notifying it that the conversion happened and providing the associated metadata.
The postback flow begins when a user clicks an ad. The ad network records the click along with a unique click identifier and device information. When the user later installs the app and the attribution provider determines which network deserves credit, it constructs a postback URL containing the click ID, event details, and any additional parameters. This URL is called server-side, meaning the communication happens entirely between backend systems without any involvement from the user's device.
This server-to-server architecture is what makes postbacks reliable. Unlike client-side tracking methods such as pixels or JavaScript tags, postbacks are not affected by ad blockers, browser cookie restrictions, app backgrounding, or network connectivity issues on the user's device. The data transmission happens between servers with stable connections, retry logic, and error handling, making postbacks the backbone of mobile attribution data flow.
Postback Configuration and Setup
Setting up postbacks requires coordination between the advertiser, the MMP, and each ad network. The process typically starts with the ad network providing a postback URL template, a URL with placeholder macros that the MMP populates with actual values when firing the postback. Common macros include {click_id}, {device_id}, {event_name}, {revenue}, and {campaign_id}.
The advertiser configures these postback templates in their MMP dashboard, specifying which events should trigger postbacks to which networks. A basic setup might send install postbacks to all networks, while a more advanced configuration sends specific post-install event postbacks, purchases, subscriptions, level completions, to networks that use this data for optimization. The granularity of your postback configuration directly impacts how well ad networks can optimize delivery for your campaigns.
Authentication and security are important considerations. Postback URLs should use HTTPS to encrypt data in transit. Many networks support authentication tokens or signatures that verify the postback originated from a legitimate MMP. Without authentication, a malicious actor could fire fake postbacks to inflate conversion counts or manipulate network optimization algorithms. Verify that your postback setup includes appropriate security measures for each network integration.
Postbacks in the Attribution Chain
Postbacks serve multiple functions in the attribution ecosystem beyond simple notification. For ad networks, incoming postbacks are the primary signal used to optimize campaign delivery. When a network receives install postbacks, its machine learning models learn which user segments, placements, and creatives drive conversions. When it receives revenue postbacks, it can optimize for value rather than just volume. The quality and timeliness of your postbacks directly affect how well networks optimize for your goals.
For billing and reconciliation, postbacks serve as the source of truth for conversion counts. The number of install postbacks an MMP fires to a network should match the number of attributed installs in the MMP's reporting. Discrepancies between MMP reports and network-received postbacks are a common source of billing disputes. Regular reconciliation, comparing MMP-reported conversions against network-received postbacks, helps catch configuration errors, delivery failures, and data discrepancies early.
Linkrunner streamlines postback management by handling the configuration, delivery, and monitoring of postbacks across all your integrated ad networks from a single platform. Instead of manually configuring postback templates for each network, growth teams can set up event forwarding rules that automatically send the right conversion data to the right partners, with built-in retry logic and delivery monitoring to ensure no conversion signals are lost.
Event Postbacks and Optimization
While install postbacks are the baseline, event postbacks unlock the real power of network optimization. When you send post-install event data back to ad networks, purchases, subscriptions, registrations, tutorial completions, you give their algorithms the signal they need to find users who will not just install but actually convert on your key business metrics.
The choice of which events to send as postbacks is strategic. Sending too few events limits the network's ability to optimize. Sending too many creates noise and can confuse optimization algorithms. The best practice is to identify 3–5 key events that represent meaningful progression through your conversion funnel and configure postbacks for those specific events. For an e-commerce app, this might be: add to cart, first purchase, and repeat purchase. For a subscription app: registration, trial start, and paid conversion.
Revenue postbacks deserve special attention. When you include revenue values in your postbacks, networks can optimize for return on ad spend (ROAS) rather than just conversion volume. This is a fundamentally different optimization target that typically produces higher-value users at the cost of lower volume. Configure revenue postbacks with accurate values, including currency codes, and verify that the revenue data flowing through postbacks matches your internal analytics. Discrepancies between postback revenue and actual revenue undermine the optimization signal.
Postback Troubleshooting
Postback failures are one of the most common and impactful technical issues in mobile marketing operations. When postbacks fail, ad networks lose visibility into conversions, their optimization degrades, and billing discrepancies accumulate. Systematic troubleshooting requires understanding the common failure modes and their symptoms.
URL formatting errors are the most frequent cause of postback failures. A missing parameter, an incorrectly encoded character, or a wrong macro name can cause the receiving server to reject the postback. Always validate postback URLs using the network's testing tools before going live. Most networks provide a postback validation endpoint that returns detailed error messages for malformed requests.
Timing issues can also cause problems. Some networks impose time limits on postback acceptance, if a postback arrives more than 24 or 48 hours after the attributed click, it may be rejected. This can happen when attribution windows are long or when MMP processing delays push postback delivery beyond the network's acceptance window. Monitor postback delivery latency and investigate any systematic delays. Server-side issues like endpoint downtime, rate limiting, or authentication token expiration require coordination with the network's technical team to resolve. Maintain a monitoring dashboard that tracks postback delivery success rates by network and alerts on anomalies.
