I used to use SparkPeople to track exercise/weightlossly stuff, but MyFitnessPal is so much easier. There is a website and an app (for both Iphones & Android phones). I especially like that I can enter several foods at once rather than one at a time like SP.
Just wanted to share!
Here's the link to the website, if you're interested: http://www.myfitnesspal.com/