I'm using the cloud version of QuickBooks for book-keeping. Their UI is not as pretty as Xero, but it is way more functional. They allow you to split up your book into nested sub-accounts, which may come in handy as you grow.
I've quite enjoyed And.co. I was an early beta user and I'm still paying til this day. It's not as robust as something like Quickbooks but they remind you about taxes and even have hookups to actual CPAs should you need them.