Update 6/8/2016: Pokemon GO is finally here in Singapore! And yes, it seems that most of the places in Ingress are also Pokemon stops.
As the original article was written before Pokemon Go was released, you may find the main contents irrelevant. So here’s what you need to know:
Based on my personal experience at Bishan Park, Serangoon, Botanic Gardens and VivoCity, you should check out VivoCity if you want the most fertile catches–you can find hoardes of Magikarps (you need a hundred of these to evolve a Gyarados), a number of Tentacools (and Tentacruels as well), Slowpokes, Horseas, Psyducks (and the occassional Golduck), Zubat (and the occassional Golbat), Meowths and many more. Not to mention, there are more than seven Pokestops at the rooftop of VivoCity alone, in very close proximity to each other. On National Day, most of these stops had lures, making it very fertile land indeed.
After what seems to be an interminable wait, rumour has it that Pokemon GO is all set to be rolled out in Southeast Asia within the next couple of days. If you want to stay ahead of the game, you may want to start scouting for possible PokeStops and Gyms scattered across Singapore. This is something you can do legally even before the game’s released.