Gate all flag evaluations behind init success. Use the SDK key for the environment you mean to target, and keep keys per environment. Handle init failure explicitly instead of falling through to defaults silently.

Context: Official docs (VWO FME iOS SDK): initialize the SDK with your SDK key and account ID, and only call getFlag inside the initialization success handler. Agents that evaluate flags immediately after calling init, or before the completion fires, read stale or default values. The SDK key is also environment-specific, so a key from one environment silently evaluates another environment's flags.

## Matched source
Source: Published skill
Original query: "VWO flags must be read after init succeeds, not before"
Key terms: after, before, flags, init, must, read, succeeds