I have tried many, including scheduleOnce, Calendly, Appointy, and a few Wordpress plugins, but hands-down, this beats them all. There are certain options and features I'd like to see implemented still, but this still beats everything I've used.
One of my main criteria was to make sure the user experience was as flawless as possible. 10to8 makes the user interface nearly flawless. On top of that, it's aesthetically pleasing.
The first week I used it, a client got to my booking page, booked their first session, paid for it, and received a reply - all without my involvement!
I had reservations because of their integration with Stripe (a pay company I've never used), but have had zero issues getting paid. And Stripe, I'm finding, is a bit easier to use than PayPal.
I've written to support at least twice, and both times received detailed replies on how to do what I needed to do. And if what I wanted wasn't built in already, there was always another way to accomplish a task.
On top of all this, I'm now using Zapier to connect 10to8 with my CRM. Now whenever a new client books a session, their contact info is sent to my CRM automatically.
Finally, they are continually finding ways to improve the system. AND they have a Facebook group where their users can share and ask questions.
Oh, almost forgot, I am also using their excellent Wordpress plugin.
With the ability to see immediate history of all interactions with your client in a chat-like column, the synchronization with Google Calendar (and others), the use of Zapier to integrate and communicate with other programs, and the seamless user experience, I am thrilled I kept testing other programs until I ran into the game changer that is 10to8. I Love it.
Ease of use