How do I tracky Couch to 10k?

I'm not sure how to track my calories for my couch to 10k app that I have on my phone. The first 8 weeks are exactly like couch to 5k, then it starts increasing the running time even more. I'm on week 2 now, but wondering if anyone is doing something similar & how they are tracking it. I have been using the "race walking" since I am doing a combo of brisk walk & jogging. Should I use something else?