According to ESRI Class changes in the ArcGIS SDK for Windows Mobile 3
LegendSwatch Replaced with LegendItem in FeatureCaching namespace.
I am converting an older Windows Mobile to the new SDK and having trouble finding references to converting the MobileCacheMapLayer LegendSwatch from:
IList<LegendSwatch> legendswat = mclayer.Layer.Renderer.GetLegendSwatches(Color.White, 16, 16);
to similar code using LegendItem in the new FeatureCaching namespace (C#).
Ref: ArcGIS Runtime for Windows Mobile