For every guide that costs money, there’s typically an almost-as-good freebie at the other end of a quick web search, but if you want the best iOS guide to Batman Arkham City — the official licensed version, from illustrated reference book publisher Dorling Kindersley (DK) no less — Batman Arkham City Official Map App is peerless. For $2.99, you get absolutely everything: Riddler trophies, riddles, 350 collectibles, scrollable/zoomable maps for every area and, critically, a tracking option that lets you check things off as you go.
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