Disclaimer: I develop http://makeplans.net http://makeplans.net which is also an online appointment booking solution (SaaS). I don't think any of our clients w

Disclaimer: I develop http://makeplans.net http://makeplans.net which is also an online appointment booking solution (SaaS). I don't think any of our clients would be interested in hosting their own software. Most of our clients don't even have an IT-department. But sure there is a market for open-source solutions as well. Particularly if you need customisation or to be integrated with offline applications. But with a good API and API-connecting services like Zapier integration is becoming less and less a valid point to host your own software. I never heard about Easy Appointments before, thanks for the link it actually does look quite good unlike most other open source business applications. There a few other open source solutions out there but it is more like Wordpress plugins.