HotCodePush glossary of over-the-air update terms

Every term HotCodePush uses, from channel and bundle to fingerprint and rollout, with what each one means and what it is not.

Every term HotCodePush uses, defined once, with what it is not to be confused with. The words are the same in the console, the CLI, the API and the SDKs, and each term links to the page that owns it.

Term	Definition	Not to be confused with
App	One product of an organization across its platforms. It owns channels, bundles, releases and devices. Its id is public and stamped into the binary.	The store listing. The binary.
Audience	The devices a set of conditions reaches, seen in the last 30 days, and the preview before a release exists.	A marketing segment. The channel's whole fleet.
Auto-pause	The rule that pauses a release when more than 5 percent of at least 50 applied updates failed, with 95 percent confidence. It is set per channel and overridable per release.	A rollback. Pausing a channel.
Binary	A store build: platform, version and build number, created by the build step with the bundle it ships and its fingerprint.	A bundle. A release.
Binary version	The store version and build number of the native app, which the `binary` condition ranges over.	The bundle's version label. The fingerprint.
Bundle	The uploaded files of one web or JavaScript build with a manifest, immutable, carrying a version label and a fingerprint. The console shows `#42 · 1.4.2`.	A release. The binary.
Channel	The named stream of releases a device follows, one per device at a time, set in the build and switchable at runtime.	An environment. A deployment key. A Git branch.
Delta	The archive a device with a base downloads in one request: the files the base lacks, built per base once a release runs.	The pack. The patch, which travels inside a delta.
Device	One install of the app, identified by an anonymous id the SDK generates on first launch. It reports its binary, SDK, fingerprint, channel and attributes when they change.	A user. A phone, since a reinstall is a new device.
Embedded bundle	The bundle compiled into the store build, which a device resets to. It carries no bundle number.	A bundle downloaded over the air.
Fingerprint	A hash of a project's native contract, read from the lockfile. It is stamped into the binary, computed for the bundle, and the condition every release carries.	Device fingerprinting, of which there is none. The build number.
Hot code push	The technique behind an over-the-air (OTA) update. HotCodePush, one word, is the platform.	HotCodePush, the product.
Index	The file a device fetches on a check: the channel's releases with their conditions, the revoked ids and whether the channel is paused.	The bundle manifest. The app's channels index, which lists discoverable channels.
MAU	Monthly active devices, the billing unit: a device counts for an app the first time it checks in a calendar month.	A user with an account. The channel's active devices, which count 30 days.
Over-the-air (OTA) update	Updating the JavaScript, HTML, CSS and assets of an installed app without a store release. Also called a live update, code push or hot code push.	A native update through the store. A push notification.
Pack	The full archive of a bundle, every file, which a device without a base downloads in one request.	The bundle. The delta, which carries only the files one base lacks.
Patch	The byte-level difference of a React Native or Expo main JavaScript bundle against the base's, inside a delta when it is smaller than the file.	The delta.
Platform	The native target a bundle runs on: `ios` or `android`. A React Native bundle serves one, a Capacitor web bundle two.	The framework. The OS version, which is a condition.
Readiness gate	The check after every apply: the app's first render, or `notifyReady()`, within `readyTimeoutSeconds` confirms the update, and a timeout or a crash reverts to the last confirmed bundle.	A crash handler, which the SDK does not install. The apply strategy, which picks the moment.
Release	A bundle assigned to a channel, numbered per channel, with conditions, a rollout percentage, a mandatory flag, notes and a state.	A store release. The bundle itself.
Rollout	The share of a release's audience that receives it, 0 to 100 percent. A device that has the release keeps it.	A/B testing. A channel.
Update	What a device receives: the newest release it qualifies for, downloaded, verified and applied. A device applies, confirms or fails an update.	A release. A check, which may yield no update.

Glossary