Always ensure you're running the latest version of PayAnywhere. To check:
Android: Settings→Tutorials and Support→Build Version (at the bottom of the screen)
Try a device restart.
Avoid using phone or device cases when using the reader. This could prevent the reader from being plugged in properly.
Make sure the device volume is turned all the way up.
Card Reader Cannot Connect/Initialize
Ensure the phone or device volume is at maximum volume.
Ensure PayAnywhere and the bumper is facing the same way as the screen when you plug it in.
Card Swipe Issues
Ensure the card reader is plugged in at the proper orientation.
Holding the card with the magnetic strip facing up toward the PayAnywhere logo, swipe the card from right to left using a swift, firm action. Some users report a distinct sound of "Snick!" when the card swipe is done correctly.
The app will prompt the user if the card swipe was done incorrectly. It sometimes takes a few tries to get the technique down.
Some users have found that bending the card slightly when swiping, so that the card has better contact with the mag stripe reader on the inside, results in a better swipe result.
As with all swipe readers, older cards will have a more difficult time.
If the card has a chip in it, the user MUST use the Chip Insert function. Swiping the card will result in an error.