To delete a counter, first swipe your finger on the counter from right to left to expose the Delete button.
Once you delete a counter, it cannot be restored.
If you have iCloud Synchronization enabled, tapping the button will present you with a choice of how to dispose of the counter; tapping elsewhere on the screen will cancel the deletion.
Choosing “Delete Everywhere” will remove this counter from all synchronized devise. Choosing “Hide Here” will hide this counter on this device but leave it active on your other devices. Use the “Restore Hidden Counters” feature on the Settings page will restore any previously hidden counters.
If, however, iCloud Synchronization is not enabled, then tap the button and the counter will be removed; tapping elsewhere on the screen will cancel the deletion.