I thought a little while ago about getting or making a shoulder holster for my phone, and a back scabbard for my umbrella, but I imagine both of those things would cause some unease for people around me. After all, if you see a shoulder holster, you're not going to think "phone" first, are you? So perhaps a better option is a low-slung hip holster instead. Maybe someday.
Mokalus of Borg
PS - I might still get away with the umbrella on my back.
PPS - As long as it doesn't have a sword handle.