[adamt]

I am not a lawyer but have been involved in various trademark registrations and disputes.

The trademark is for the concatenation 'whoshere'. Given that both are common words obvious to the topic I would have thought the interpretation would be very narrow and 'who's near me' is suitably different. I certainly don't think you should give in to their somewhat extortionate demands.

[ajross]

Even given a very narrow interpretation, "here" and "near me" are basically synonyms. And as I understand it the apps are very equivalent too, they're selling the same product under a near-identical name.

"Red" and "Hat" are common words too, but you'd never get away with trying to sell a linux distro named "Red Cap".

[fla]

You'd never get away with trying to sell a linux distro, anyway :)