I’ve tried Thunderbird and wasn’t convinced… My work life is basically email, and I’ve tried several email apps over the years, a lot more than most people. I’ve found Postbox on desktop and Spark on mobile to be the magic pair for me so far. Unless Postbox fails me, I don’t think I’ll bother trying anything else anytime soon… Though I’m open to suggestions for mobile, since there’s room for improvement with Spark.