Some tips to tackle the loss of Bluetooth connection between the iPad and scanner, printer or card reader:
1. This could be happening due to the iPad going into sleep mode, so try to increase the time it takes to auto-lock at Settings > Display and Brightness > Auto-lock.
2. Make sure the devices (iPad and scanner, printer or card reader) are in close proximity to one another.
3. Avoid using your wireless devices near common sources of interference like power cables, microwave ovens, wireless video cameras and cordless phones.
4. Reduce the number of active devices that use the same wireless frequency band.
5. Configure your Wi-Fi router to use a different Wi-Fi channel or have it scan for the channel with the least interference.
6. If you’re using USB 3 devices with your computer:
- Use a high-quality, shielded USB cable with each USB 3 device.
- Move your USB 3 devices—including any USB hubs—farther away from your wireless devices.
- Turn off any USB 3 devices that aren’t in use.
- Avoid physical obstructions in the path of your wireless signal.
7. Remove old Bluetooth connections.
8. Update the hardware’s firmware.