You Can Also Connect Zoho Invoice or Postmark With 1400+ Other Apps
Zoho Invoice
Zoho Invoice is an easy to use and highly customizable invoice software for small businesses. It's mobile friendly, has payment reminders and recurring billing features.
Postmark is a supercharge for your app's email. It connects directly to your application and takes care of sending, receiving and storing emails on your behalf. It's fast, easy to use and has amazing customer support.