Does the app work with no signal?
Mostly. A repair request or a message written with no signal sends itself when you are back on a network. Paying rent needs a connection, and the app says so.
From the guide Using the Seayora app as a resident.
When there is no signal
What you do with no signal is saved on the phone and sends itself when you are back on a network. A strip at the top of the app says how many things are waiting; tap it to see them. Paying, approving a sign-in and calls are the exceptions, because they only mean something at the moment they happen, and the app says so instead of queuing them.
Read the whole guide: Using the Seayora app as a resident