Weather Lah is a great weather forecaster application for your iPhone. It provide weather forecast in different areas in Singapore which is important since here it can be pouring at one place but hot like a desert at another; such as raining at Boong Keng but sunny at Raffles.
Another iPhone application I'm using is Endomondo. This will track your sport activity such as cycling: transport or competition. It's very basic and easy to understand. http://www.endomondo.com/login
Give it a try.