I'm surprised MTG Familiar ain't here. It has card search, the entire rulebook, all banned lists, life counters, deck builder, wishlist,and it also checks trade value (internet connection required.) Plus, it's card search works offline. It only shows you the text and casting cost though, so no artwork. But still, it's pretty useful and has everything in it.
UGMefolkGU
GElvesG
Casual
UBPirate ArtifactsBU
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NEWBIE
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He raged at the world, at his family, at his life. But mostly he just raged.