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not bothered about smart phone capability, just the ability of survive UK off road riding and not be stupidly expensive
Another simpler Nokia...
We have a box of old Nokia's at work - they just refuse to die unless we drown them (a regular occurrence).
E51 or E71 seem to be tough as old boots too.
Whatever the cheapest phone you can buy is (Siemens something or other generally going for £10 - that's what I have), inside a ziplock bag. Or if you're feeling posh, or particularly likely to get immersed, inside a drybag - they gave some out at Mayhem this year, though sadly I've misplaced mine, or I have a proper triple-sealed job I take sea-kayaking.
Those 5210s weren't really all that. More rugged than a normal phone maybe, but they were only splash-resistant not waterproof, I managed to kill mine by getting it properly wet - you still needed to use a waterproof bag if you wanted it to survive a dunking.
more waterproof than my Motorola Atrix, 2 busted in 12 months, the rubberised bit of the 5210 was excellent as i'm always dropping the phone or accidentally putting it into a pocket with keys etc
Think they still do the later 5500 sport.
Found mine once after it was ringing in the bottom of the new toilet I was fitting causing nice ripples in the water 😛
Samsung GT B2100
Tougher than a tough thing. Cheap as the chips these days.
I've got a iPhone with a griffin case - can't remember what its called but it fell out of my pocket at 70mph ish and its still fine
also dropped into 6ft of snow coming back from a bar in alps and found the next morning still fine
I'm 3 years into a Nokia e71, a bit clunky but records GPS accurately. Solid and reliable and not too bad a battery, by smartphone standards...
Samsung Solid M110 is xcellent may have one for sale 😉
Isn't the Defy weatherproof?
If you want proper rugged, google JCB phones.