It is possible to manually check out an item using your Dashboard.
To do this, go to your Item Log and click on the item's ID number. Click on the "Actions" button on the upper righthand side of the Item Detail Page.
Then click "Manually Check Out Item."
Type your name in the text box and tick the box that says "I confirm that this item should be marked as checked out." Click "Mark as checked out" to complete the process.
You should only use this when you truly forget to check out an item using the app. This is not meant to replace the check-out process in the app.