I use mine for both running and biking.

for running i brought a cheap arm strap off of ebay ages ago for my 5800. it was big enough to squeeze my N97 in when I upgraded and even managed to stretch a little bit more to fit my N900 =)

I wouldnt want to keep it in my pocket bouncing around though.

ecoach is great but i miss the community features of sportstracker.

the only things that worries me are rain and when i'm on my bike I worry about falling off and landing on my phone. not that its ever happened but I get paranoid with this beauty =)