Renting bikes here is the best way to see Singapore. If you use the app based city bike shares, they are poor quality, no gears, heavy, you must park them in designated parking spots which seem to be mostly in the downtown area and are limited by availability of the bike. Dualcircles bicycles are top quality and have many options for add-on accessories such as phone holders and lights. If you want an immersive way to see the city then I suggest going by bicycle. It will also end up being cheaper than the bike shares if you use it as your main form of transportation.
Additionally, Jasper of Dualcircles was friendly and very accommodating on short notice when we booked the bike. He gave us expert suggestions on navigating the city and places to see.
We had the best time. Highly recommend.