@Barry Smith
Those are all completey different services becasue of the functionaliy they all have or don't have. Vumber is easy to use but is limited in functionality. CallRail has a lot of features but is difficult to use and has a learning curve. Ring central doesn't provide analytics so it is more of a voicemailbox system like google voice with more features.
The bottom line is anytime you integrate a thrid party application with Podio or any other system there are going to be a lot of moving parts. If you could find one system that has the CRM and the call tracking in one place then would be much better for you,,,, the user.
We use one that has both the CRM and call tracking analytics built in as one service and also has functionality for recruiting and managing referrals like property locators, attorneys, etc...
The key is to use a system that is built for real estate not the general public that needs to be customized for real estate. I hope this helps!