You’ve switched to an iPad Pro and might need more than an USB-C to 3.5mm headphone jack, you might also need an HDMI adapter to do presentations or an USB-A connector for other peripherals like a DLSR camera. Apple has an array of single adapters but an alternative is an USB-C hub. Satechi has a very cool Aluminum Type-C Mobile Pro Hub. It features a 4K HDMI display port, USB-A, USB-C and a 3.5mm headphone jack.
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