I’m lover of special rooftops/views and obsessed foodie so the list is mostly based on views, food and kinda authentic places or what I consider it to be))

I also have to say that even after visiting Sing may times, I’ve been to the same places almost all the way, so it’s could be pretty biased:

Rooftops:

– 1-Altitude (one of most famous rooftop in Sing, watch out dress code!)
– Level 33 (perfect view & their own craft-beer, the owner is german)

Views:

– Marina Bay Sands (must have, one of the best views worldwide)
– Hong Lim Park (very cool mixture of urban & green)
– Gardens by the Bay (general must have, but take a look at it at night)
– East Coast Park (park + view)

Food/Gourmet tipps (there are more, but I can’t list all of them):

– People’s Park Food Centre (most authentic foodcourt in Sing)
– East Cost Seafood Center: UDMC Seafood / Jumbo Seafood (best seafood in Sing, get chilli crab!)
– Symmetry (nice alternative one)
– Pelican Seafood Bar (great view on Marina + Vicky the best host of Sing)))
– Taj Authentic Indian Cuisine (good indian food)
– Raffles Place (get a famous cocktail)
– Marina Food Loft (good food & view)
– Hilltop Japanese Restaurant (good japanese one)
– Saint Pierre (decent french one)
– Ding Thai Fung (proper chinese one)
– No Signboard Seafood (decent seafood)

Spiritual:

– Sri Mariammam Temple

Authentic:

Little India (indian district)
Golden Mile (very rare thai district)
Chinatown (as the name says)
Raffles Place (historic & charismatic place with its great vintage atmosphere)

General tourist places:

– Merlion
– Flyer
– Sentosa
– Fountain of Wealth
– Visual & water shows
etc etc… are not on my list ’cause everybody knows them and visits them…

I don’t recommend Bugis, ’cause it’s muslim district with all related issues.

Important: get EZLink-card at the day time for metro & use taxi at night.