One thing I miss from the pre-touchscreen era: never-changing UI with soft-realtime guarantees. When e.g. using my old K800i, I had memorized sequences of actions and delays (eg: "down, 3, ok, wait ~1 second, down, down, ok"). The delays were consistent. This meant I could operate my phone without looking at it, without even pulling it out of my pocket. This is impossible in the smartphone era, not just because UIs change, but because delays are completely unpredictable.