You can check your balancewith the Leap Top-Up App on your mobile phone. Just hold your TFI Leap Card to the back of your phone.online as well as previous transactions on your card. (It can take up to 24 hours for transactions to appear on your online account).by asking for a balance enquiry at any TFI Leap Card retail agent or by placing your card in the card pocket at any Luas/DART/Commuter Rail ticket machine and following instructions on the ticket vending machine screen.