App Store and Play Store review rejections have a way of surfacing guideline violations that were easy to miss during development, and the review cycle delay makes each one costly in a way that's disproportionate to how small the actual violation usually is. A rejection over an imprecise permission-usage description can cost several days of round-trip time even though fixing the actual issue takes ten minutes, and that asymmetry between the size of the problem and the size of the delay is what made this worth solving properly rather than just being more careful by hand.
We set up an agent that checks a build against current store guidelines before submission, reviewing permission declarations, metadata, screenshots, and privacy disclosures against both stores' published policies before anything goes anywhere near an actual review queue. It's caught permission-usage descriptions and metadata issues that would otherwise have meant a multi-day round trip through manual review, including a couple of cases where a permission request had been added for a feature that shipped later than expected, leaving a stale, now-inaccurate justification string sitting in the app's metadata that nobody remembered to update.
It doesn't guarantee approval, and we're careful not to describe it that way internally or to clients, since both stores' guidelines get interpreted with a fair amount of human judgment on the reviewer's side, and no automated check can fully anticipate that. But it's meaningfully cut our rejection rate on first submission, and just as importantly it's cut the time our mobile team spends manually cross-referencing a build against a guidelines document that both companies revise more often than anyone can reasonably keep up with unassisted.
Keeping the agent's guideline knowledge current has been the main ongoing maintenance cost, since both platforms update policy language periodically without much fanfare, and a stale reference set defeats the purpose almost as thoroughly as not having the check at all. We update the underlying guideline reference on a regular cadence and treat a stretch of unexpected rejections as an immediate signal that the reference has drifted out of date somewhere, which has happened a small number of times and been quick to diagnose and fix once we knew to look for it.
The check runs as a required step before any build is handed off for submission, not as an optional tool a developer can skip under deadline pressure, which was a deliberate decision after watching exactly that skip happen once during an early trial when the check was still opt-in. A developer confident the build was fine skipped the pre-flight check to save a few minutes, and that build was rejected for a screenshot showing a debug overlay that had accidentally been left enabled, something the automated check would have caught immediately and a human reviewer, tired at the end of a release cycle, simply didn't notice.
We've extended the same check to cover a few client-specific concerns beyond the stores' own published guidelines, things like making sure a client's required legal disclosures appear on the correct screens, since those are exactly the kind of easy-to-forget detail that doesn't show up in Apple or Google's guidelines but still causes real friction, usually in the form of a client complaint rather than a formal rejection, if it's missed. Treating the pre-submission check as a general-purpose "things we've been burned by before" list, rather than strictly a guidelines-compliance tool, has made it more useful than we originally scoped it to be.