This is one of my favorite restaurants in Singapore. My friends and I love to hang out there, especially during happy hour. Happy hour is from 6 to 9pm every day, and draft beer, tequila drinks, and house wines and spirits are on a buy one, get one free basis.
This restaurant/bar is outdoors. You can choose to sit at the bar, on the stools by the high tables (there are a few long tables and you share with other people), or outside. Wednesday, Friday, and Saturday nights get pretty busy, so you should definately make a reservation. The interior of Cafe Iguana is very impressive, one of the nicest looking bars in Singapore probably.
The staff are very friendly but the service can be a bit slow sometimes because it gets busy. The food is actually really good, so it's not only the drinks I go there for. The Prawn Fajita and Tequila Chicken Grill are my favorites.
You probably don't want to go to Cafe Iguana if you only have a few days in Singapore because there's plenty of good local dishes that you should try. But if you do have a night to spare away from the local food, check this place out.