Hi UCCStewardship,
I believe the recommended and Square supported dongle for the magstripe reader you have is a USB-C to Headset Jack which can be found here. Most likely anything else probably won't work nor would be supported. As a possible work around depending on which iPhone model you have, you could use a wireless charger. That would give you both, just in a different configuration. Or you could simply everything by using Square's contactless and chip reader, it connects via Bluetooth thus freeing up your lighting port so you can still charge your phone. When you choose to use only a magstripe reader, there's the liability shift to consider. Suggest reading about it here - it's something to consider. Just my thoughts here, but the contactless and chip reader is very good solution and has worked quite well for us.
