Work with function buttons in Logic Pro for iPad
Logic Pro for iPad provides groups of function buttons for a variety of editing tasks. Function buttons are available in the Tracks area, the Live Loops grid, the Audio Editor, the Piano Roll Editor, and Step Sequencer. In those working areas, function buttons are located in the middle of the menu bar for that working area. For example, the Tracks area menu bar has function buttons for editing regions using Trim, Loop, Split, and Stretch edit modes.
In general, you tap a function button to turn on its edit mode, then tap or otherwise interact with regions, cells, MIDI notes, or other items in the working area to edit them. Tapping a function button to turn on an edit mode turns off the previously active edit mode for the working area.
Use function buttons as momentary buttons
Function buttons can also be used as momentary buttons. To use a function button as a momentary button, you touch and hold the button, then perform an editing operation without releasing your finger. After completing the operation, you release your finger, and the function button that was selected before the momentary one you just used remains selected. For example, with the Trim button selected, you can touch and hold the Split button, split one or more regions using the Scissors tool, then release your finger from the Split button, and the Trim button remains selected.
When you touch and hold a function button but release your finger without performing any editing operation, the button becomes selected, and its edit mode is turned on.
Use modifier buttons
In addition to the function buttons, Logic Pro provides modifier buttons that modify the functionality of the edit modes. The Multiple Select and Copy buttons are located to the right of the function buttons in the Tracks area, the Audio Editor, the Piano Roll Editor, and the Mixer (in the Mixer, both modifier buttons are available in Setup mode, but only the Multiple Select button is available in Mix mode).
Multiple Select button: When the Multiple Select button
is selected, you can select multiple items by tapping them. Tapping an item selects it (or deselects it, if it’s already selected) without deselecting other selected items.Note: After selecting items using the Multiple Select button, be sure to deselect the button before using one of the edit modes.
Copy button: When the Copy button
is selected, dragging an item creates a copy rather than moving the item.
In addition, the Stepped Automation button 
is available when Automation view is turned on in the Tracks area. See Stepped automation curve.
The Multiple Select and Copy buttons can also be used as momentary buttons. For example, you can touch and hold the Copy button, drag a region to create a copy, then release your finger from the Copy button and drag regions without creating copies of them.
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