We are currently two but we will be three starting next year. That will definitely help!
We want the backend to be very transparent for the user. This means that if there is any downtime on the server, you will still be able to use the app, scan documents, create PDFs, export them etc.
However, it has always been our philosophy to take our time to reduce the operational load as much as possible since our time is so precious. We have quite some experience with that having run the business as a side-project for a while before going full time on it. Running a boostrapped, profitable company also helps in that you don't have any external pressure.