Yes. As of August 2012, Final Draft Writer is available for iPad for $49.99.
FDX Reader by Quote-Unquote Apps can be used to read Final Draft 8 documents (.fdx files) on the iPad or iPhone, but is not a script editor.
Answer Index
script
scriptwriting
screenwriting
screenplay
formatting
terms
film
presentation
structure
business
writing
software
TV
WGA
Final Draft
guild
characters
length
credits
FDX
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union
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dramatic theory
outlines
arbitration
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fountain
pdf
highland
producers
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Celtx
guru
Movie Magic
rights
agents
awards
pitching
short film
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iPhone
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prelap