I never called my Ts except when we had pre-arranged phone sessions, and rarely text (mostly just when I had to cancel last min and wanted to make sure they saw it). I emailed a lot with both of them though and found it very helpful, including actually breaking a compulsive online interaction habit. Now, if I were to look for a new T, I would always ask what their email policy is and would not choose one who does not allow/read emails. It was seriously the best, most productive part of my therapy, along with discussing the emailing in sessions.