The following article provides suggestions and guidance for selecting on-site badge printers.
iOS devices require AirPrint-certified printers: https://support.apple.com/en-us/HT201311
Note: Unlike Android, no additional work is needed to custom-fit any printer not found on the list above.
Google Cloud Print is no longer supported by Android Devices, making this dependent on the Printer you own and how they work with Android Devices. It is not recommended that Android Devices are used for Check-In with On-Demand Badges unless you are 100% sure and have tested that your Printer works with your Android Devices.
If you are encountering issues where the printer cannot be seen by the device, this may be because of the type of network you are connecting to. When working with WiFi and Badge printers, the network needs connected Devices to be "Discoverable" by setting the wireless router for AP Isolation "off". This is sometimes called Client or Wireless Isolation.
Many hotels or areas that provide WiFi connections have this setting On by default, preventing one device connected to it from seeing any other connected devices. If you are setting up a connection at a venue, you would want to ensure that the venue administrators know that this setting should be turned off for the network you are connecting to and that the devices need to see each other on the WiFi network.
Another option some of our customers have used is to bring their own WiFi Router on-site. Customers can then connect their WiFi Router to the Venue's internet and have their devices connect to their router (which allows controlling the settings for the WiFi connection to that router). While this adds another layer of complexity, it ensures you have the correct type of network even in a location or venue that cannot provide it.