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LabVIEW optimizes PDA and Touch Panel VIs for data size, speed, and code size, in that order.

PDA devices run on battery power. A user typically runs PDA applications for short intervals and then expects the device to switch to low power mode until the next time he or she needs it.

To conserve battery resources, include a Wait for Front Panel Activity function or an Event structure in a PDA VI to create a wait state to save battery power. Adding a wait state allows the PDA VI to go to sleep if you do not tap the screen for the duration you specify in the preference settings on the PDA device.

PDA and Touch Panel VIs use cooperative multitasking. Therefore, you can design PDA and Touch Panel VIs to have parallel loops on the block diagram. One loop runs for a time slice of approximately 50 ms, and then another loop runs for a time slice. PDA and Touch Panel VIs automatically use cooperative multitasking when you use two or more nodes that a wire does not connect. However, PDA and Touch Panel VIs with parallel loops run slower than VIs with serial loops.

If you set the execution priority of a PDA or Touch Panel VI to subroutine, LabVIEW serializes execution of the VI. The PDA or Touch Panel VI runs faster, but the user interface does not get any CPU time, and the application might become unresponsive. Place a Wait Until Next ms Multiple function on the block diagram to accommodate this limitation.

Using subVIs in PDA and Touch Panel VIs can affect parallel execution, which affects performance.

Using 2D front panel controls instead of 3D front panel controls in Touch Panel VIs can increase performance because 2D front panel controls have quicker refresh rates than 3D front panel controls.