DroidEdit Pro (code editor) v1.14.9 APK

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You should try the ad supported DroidEdit Free before buying this app. The ad free version has exactly the same functionality as the paid version except it doesn't have SFTP support, Dropbox support, Custom themes and root mode.

Features:

Syntax Highlighting for several languages (C, C++, C#, Java, HTML, CSS, Javascript, Python, Ruby, Lua, LaTeX, SQL, ...)
Several color themes
Infinite undo & redo
Search & replace