# facebookarchive/pop

An extensible iOS and OS X animation library, useful for physics-based interactions.

Repository: https://github.com/facebookarchive/pop
Canonical: https://ross.abutalabs.com/products/pop
Language: Objective-C++
License: NOASSERTION
License Family: other
Archived: true
Last push: 2020-01-02T19:13:40+00:00

## Health v2 (maintenance only)
Score: 10/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 8, longevity 100
- inputs: {"age_days": 4539, "days_push": 2435, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: archived, no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 19542, forks 2852 (observed 2026-08-28T04:11:28.805276+00:00)

## What it is
Pop is an extensible animation engine for iOS, tvOS, and OS X that supports both static animations and dynamic spring/decay physics-based animations. It integrates with Objective-C or Swift codebases and can animate any property on any object.

## Use cases
- add physics-based spring animations to iOS views
- create decay animations for scrolling interactions
- animate arbitrary properties on any object in Swift or Objective-C
- build realistic interactive animations like Facebook Paper
- add animations to tvOS apps

## When to choose
- building iOS, tvOS, or OS X apps needing spring/decay physics animations
- working in Objective-C or Swift codebases that need a mature, well-tested animation engine
- needing to animate arbitrary properties beyond what Core Animation offers out of the box

## When to avoid
- targeting platforms other than Apple's (iOS/tvOS/OS X)
- starting a new project, since the repo is archived and no longer actively maintained
- needing SwiftUI-native animation APIs

## Facets
- artifact type: library
- maturity: maintenance
- function: animation
- domain: mobile-development, graphics
- platform: cpp
- tags: objective-c, physics-based-animation, spring-animation, apple-platforms, facebook, ios, macos, swift

## Member repositories
- facebookarchive/pop (main) score 10

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:11:28.805276+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T17:00:05.377223+00:00, confidence not recorded.
  - readme: https://github.com/facebookarchive/pop (fetched 2026-08-28T04:11:28.805276+00:00, sha 8741308c5331)
- Data as of 2026-08-30T08:39:29.467469+00:00.