Packaging SDKs for Mobile Destinations
Minimizing the size and complexity of mobile SDKs is a priority for Segment. That's why Segment's core Mobile SDKs are small and offload as much work as possible in handling destinations to Segment's servers. When you install Segment's light-weight SDK, you have access to the entire suite of server-side destinations.
Segment bundles certain SDKs, instead of just proxying your data to them through our servers, so that you have access to any deeper features of your destination that require direct client manipulation (like A/B testing, user surveys, or touch heatmapping) or access to rich data like CPU usage, network data, or raised exceptions. For those types of features, Segment still needs to bundle the destination's native SDK for you so you can make the most of them.
Segment's mobile SDKs are as modular as possible so that you only need to include the SDKs for tools you plan to use.
Custom builds allow Segment to offer the native functionality of all of our destinations without having to include hefty third-party SDKs by default. This gives you control over size and method bloat. Check out how to use custom builds for both Android and iOS.
To check if a destination's SDK is bundled or not, review the documentation for your specific destination.