Here you can find a list of keyboard shortcuts you can use when you connect a wireless bluetooth keyboard or a keyboard dock to your iPad. These shortcuts work in all iOS apps.
Keyboard shortcuts supported by iOS / iPad:
• Cmd+A - Select All
• Cmd+C - Copy
• Cmd+X - Cut
• Cmd+V - Paste
• Cmd+Z - Undo
• Cmd+Shift+Z - Redo
• Shift+Arrow - Select text
• Cmd+Up/Down - Move cursor to the beginning/end of the file
• Cmd+Left/Right - Move cursor to beginning/end of the current line
• Alt+Left/Right - Move cursor to the previous/next word
• Esc - Bring up virtual on-screen keyboard
• Alt-Delete - Delete the word to the left of the cursor
• Cmd-Delete - Delete everything on the current line to the left of the cursor
iOS also supports these Emacs keybindings:
• Ctrl-A - Move cursor to the beginning of the line
• Ctrl-E - Move cursor to the end of the line
• Ctrl-F - Move cursor forward one character
• Ctrl-B - Move cursor backward one character
• Ctrl-K - Kill/delete text between cursor and the end of the line
• Ctrl-H - Delete one character to the left
Note: Unfortunately, these shortcuts are entirely provided by the iOS operating system and there's no way for third party developers to extend them with custom shortcuts.