Jordan here from Shopify :)
Depending on the supported Start Micronics receipt printer you are using, we have guides on setting these up, which will often solve any connection issues that come up:
A slow internet connection will usually not be the cause of the receipt printer showing up in your iPad's Shopify POS app though.
If you are also having a problem with the cash drawer connection, it's very likely because of the receipt printer issue, as it connects through the receipt printer, but here's the guide for setting up the cash drawer, in case it's not setup correctly.
You can also phone in or open up a chat with us for troubleshooting help, by clicking one of the links on this page.
Let me know if you have any questions! Cheers,