There's no shortage of mobile concierge services, but even the wealthy may balk at paying steep fees (or buying exotic phones) solely for entertainment advice. Thankfully, Lime & Tonic has just brought its more accessible luxury recommendation engine to the iPhone. The mobile app automatically suggests up to two premium (and sometimes exclusive) activities per day based on far more refined criteria than a typical point-of-interest app. It can recommend only those posh restaurants that cook your steak rare, for example. More importantly, it's relatively cheap to try -- signing up is free, and discounts are common. Lime & Tonic's service is currently limited to Amsterdam, Dubai, London, Melbourne, Prague, Rio de Janeiro and Sydney, although geography is likely no obstacle to the company's well-to-do customers. Besides, it could be the perfect showcase app for that future gold iPhone.