this a really good application
every week, the website will send u an email to tell u about ur baby's growth etc
"interactive" in the sense that they always update u on ur baby
there are good videos abt labour, breastfeeding etc.
Maybe you could try "Baby Deluxe" app on itunes.
You can keep track of your baby physical growth (height, weight, head size, teeth growth, etc)
You also can record you baby activities like sleep pattern, diaper change etc.
I think it's the best All-In-One Baby Apps out there.
And it's free!!