The Textor app opens files in place--so when you save the file, it saves immediately to the service / destination from which it was opened. How to create and edit plain text files in iOS with Textor ...

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The free doctape Viewer iOS app lets you open more than 80 different file types using an iPhone, iPad, or iPod touch. The app is very useful, but CIO.com blogger James A. Martin found a few drawbacks.