Quick answer: Test the update path as carefully as the game itself. Verify the patch downloads and applies cleanly, that version checks gate correctly without locking out valid players, that forced updates are unavoidable when required and skippable when not, and above all that save data migrates intact when a player jumps from an old version to the newest one.
Most players experience your game more through updates than through fresh installs, yet the update path gets a fraction of the QA attention. A patch that corrupts a save, a version check that locks out a paying player, or a forced update that loops forever does more reputational damage than almost any in-game bug, because it touches people who already committed to your game. The update flow is hard to test because it requires having an old build, a new build, and realistic player data in between. This post lays out a QA pass for the patch flow, version checks, forced updates, and the save migration that quietly decides whether your loyal players stay.
The update flow end to end
Start by treating the update itself as a feature with its own happy path and failure modes. The patch has to be discovered, downloaded, applied, and launched, and each step can fail in ways a fresh install never sees. Test on a device that genuinely holds the previous version, not a clean install of the new one, because the bugs that matter live in the transition. Confirm the player is told an update exists, that the download reports honest progress, and that applying it does not silently wipe local settings or cached content.
Then test the unhappy paths around the download. Kill the connection mid-download and confirm the patch resumes or restarts cleanly rather than leaving a half-applied build that boots into garbage. Fill the device storage and confirm the update fails with a clear message instead of a corrupt partial write. Background the game during the update and return, then confirm it recovers. These are the cases that generate angry reviews, and they are entirely testable before release if you make the time.
Version checks and gating
Version checks exist to keep incompatible clients from talking to your servers, but a careless check is a great way to lock out the exact players you want to keep. Test the boundaries explicitly: the oldest version you still support, the version one below it, the current version, and a version newer than the server expects, which happens during staged rollouts. Each should be gated correctly, allowing supported clients through and steering unsupported ones to an update with a clear explanation rather than a cryptic error or a silent connection failure.
Pay attention to the message, not just the gate. A player on an old version who is told only that the connection failed will assume your servers are down and may leave a one-star review. A player told plainly that an update is required, with a working button to get it, will usually just update. Test that the gate fires before the player invests time, ideally at launch, rather than after they have loaded into a match only to be ejected. The cost of a badly placed version gate is measured in trust.
Forced updates done right
A forced update is appropriate when an old client is genuinely unsafe or incompatible, and infuriating when it is not. Test that forced updates are truly unavoidable when required: the player cannot dismiss the prompt, cannot reach gameplay, and is given a direct path to the new version. Then test the inverse just as hard. An optional update must be skippable, must not nag on every launch, and must remember the player's choice so a player who declined yesterday is not blocked today by an overzealous flag.
The most dangerous forced update bug is the loop, where the player updates, the check still says update, and they are trapped. This usually comes from a version comparison that treats versions as strings, so build ten looks older than build nine. Test the comparison logic directly with awkward version numbers, and verify the loop cannot happen by updating to the very latest build and confirming the gate releases. A forced update that cannot be satisfied is functionally a remote uninstall, and players will treat it that way.
Save data and migration
Save migration is the highest-stakes part of any update, because a lost save is rarely recoverable and never forgiven. The realistic test is not new build reading new save, it is new build reading a save written by an old build, ideally several versions old. Keep a library of real save files from past releases, covering players at different progress levels, and run each through the new version. Confirm progress, currency, unlocks, and settings all survive, and that any schema change applies a migration rather than discarding fields it does not recognize.
Test the migration's own failure handling. If a save is from a version too old to migrate directly, decide whether you chain migrations or refuse safely, but never silently reset. If a save is partially corrupt, the new build should preserve what it can and surface a clear problem rather than overwriting the file with a blank one. Always confirm migrations are forward only and that downgrading, which players do attempt, does not let a new save quietly destroy itself when read by an older incompatible build.
Setting it up with Bugnet
Update bugs are reported in the worst possible way, by a frustrated player who just lost progress and cannot tell you which versions were involved. Bugnet's in-game report button captures game state automatically, so a report filed after a rough update arrives with the from and to build numbers, the platform, and the player's save context attached. That tells you immediately whether a migration failure hits one specific old version or every player crossing a particular schema boundary, which is the difference between a hotfix and a full rollback.
When an update crashes on first launch, Bugnet's crash reporting captures the stack trace and device context, often pointing straight at the migration code or a missing patched asset. Occurrence grouping folds the flood of identical reports from a bad patch into a single issue with a live count, so you can watch the problem spike the moment a rollout begins and react before it reaches everyone. Custom fields let you tag reports by source version, so you can filter the dashboard to exactly the upgrade path that is failing.
A repeatable update QA pass
Make the update pass a fixed ritual for every release. Maintain a small farm of devices and emulators pinned to previous versions, plus a curated set of real save files spanning your release history. Before you ship, walk each device from its old version to the new one, exercising the download, the version gate, the forced update prompt, and the save migration in sequence. It feels heavy the first time and becomes routine, and it catches the failures that no amount of fresh-install testing ever will.
Stage your rollout so the update pass continues in production. Release to a small percentage first, watch crash and report rates by source version, and only widen the rollout once the upgrade path looks clean. Keep the previous build ready to re-promote so you can halt a bad patch instantly. Updates are the one feature every player runs repeatedly, so the discipline you put into testing them pays back every single release cycle, quietly, in players who never knew anything almost went wrong.
The update path touches your most loyal players. Test from real old builds with real old saves, and never let a migration silently reset progress.