Does Resouces.UnloadUnusedAssets frees asset bundles unused resources?

I have game which uses resources as actively as asset bundles. Loading logics is quite primitive: try to load from resources, if not found, WWW.LoadFromCacheOrDownload. And I'm thinking about freeing resources.

I use Resources.UnloadUnusedAssets(), but don't use AssetBundle.Unload() method. In editor profile it seems that all unused resources from assets are properly deallocated(I don't know whether by garbage collector or by Resources.UnloadUnusedAssets method). Now I'm wondering, shall I use AssetBundle.Unload or leave it as is? Will everything be ok on phones or there always be memory leaking?

I develop for android & ios.