Are there any fees charged on transactions?

Fedi charges a flat 21 basis point (0.21%) fee on all outgoing eCash and Lightning payments as well as on deposits to Stable Balance. There are no fees to receive eCash or Lightning payments or to withdraw funds from Stable Balance.

Note that federations themselves may also elect to charge fees on transactions sent via eCash and / or Lightning, but this is up to the individual federations themselves and separate from Fedi app fees.

Lightning and on-chain network fees always apply, but on-chain transactions are not subject to additional fees beyond the network fee from either Fedi or from the federations themselves.

You will always be able to review the total fee and fee breakdown before making any payments on Fedi, regardless of the payment method. 

Lastly, note that mods, many of which are separate from Fedi and the federations themselves, may charge their own fees for different actions performed within them.