The check-in mobile apps allow you to manage your attendees during your event, you can search/filter the list of attendees, scan their tickets using the device camera or external scanner, and mark them as checked in. All using separate accounts you can create from within the Shopify app dashboard. Mobile apps are available for Apple iPhone and iPad devices, Android phone and tablet devices, as well as a web version (without camera scanning support).
The mobile check-in apps all support most major external scanning hardware. The one requirement is that they can act as a bluetooth keyboard, the scanner manuals usually call this "HID mode" and is almost always the default (and often event the only) mode available. Consult your use manual to enable this if it is not enabled.
If the scanner supports an option to scan and transfer data faster then enable that as well for most reliable scanning, this may be called "Transfer rate" in most manuals. For example, the Tera scanners can all be configured for "Fast" transfer rate by scanning a barcode in the manual.
If you have a Socket Mobile scanner, the same one Shopify sells along with for their POS hardware, and you're using an Apple device then you can enable the direct scanning integration for even better reliability. This device also supports HID mode if you'd prefer that.
As always, please contact us if you have any questions or trouble getting set up!