FrostWire Basic and FrostWire Plus are identical in all respects besides the basic version of FrostWire not having YouTube & SoundCloud Search and Download capabilities.
As of April 2015 we were told we have to remove YouTube from the list of our search engines and download sources to comply with Google Play Rules. If we wouldn't, we would no longer be able to be listed on Google Play. Shortly after, we were told to remove SoundCloud as well.
Because of a great user outcry, we choose to keep distributing FrostWire on Google Play and remove YouTube & SoundCloud entirely, effectively making the FrostWire Basic a BitTorrent Client only, but provide the more advanced users with an option use the fully featured, yet still free FrostWire Plus version.
Anybody can now download the FrostWire Plus version with YouTube & SoundCloud Search and Download functionality + PREVIEW feature for cloud sources from FrostWire's website free: http://www.frostwire.com/android