# App Platform Concepts – DigitalOcean Documentation

> Explanations and definitions of core concepts in App Platform.
- [Choosing a Plan for Your App Components](https://docs.digitalocean.com/products/app-platform/concepts/choosing-a-plan/index.html.md): Guidance on choosing the right App Platform plan for your app's components based on usage patterns and needs.
- [App Platform Build System Update Policy](https://docs.digitalocean.com/products/app-platform/concepts/platform-upgrade-policy/index.html.md): App Platform's policies for rollout of new stacks, deprecation of old stacks, and timing.