Invoice templates are great, customization is on par with other software choices. Zoho Invoice is able to integrate with the Zoho Suite, which makes it a breeze to run nearly all aspects of a small business.
I do think some features could be improved. This includes text notifications for customers, as well as integrations with more payment platforms (these are fairly limited at the moment). Also, some simple functions like merging invoices are not available. Customer portals are good, but could benefit from improved usability and more features, such as custom document sharing through the customer portal.
Zoho Invoice is a great product. Overall, we had an extremely positive experience with this software. It can be of use to nearly any small to medium sized businesses, and the integrations are countless. For even more power and versatility, it can be combined with other apps through Zapier.
We use Zoho Invoice for invoicing our customers for a music school. We have been able to cut down on paper usage and complete the invoicing process electronically. Notifications, however, go through an integration with other programs for us, since it is impossible to send SMS message to customers from zoho directly.