Probably dozens of different phone mounts.. the top of the line of Ortlieb Bar Bags let you put the phone in the top of them
in the map window. and touch screen through it.
personally as you say :
over 50, just started riding bike 3 months ago
I'd say put it in your pocket , stop, use the phone, put it back in your pocket, and concentrate on riding, and the traffic around you.
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