Baby monitors can act as a mama's second set of eyes and ears, but when you're on the go and your lil one needs a nap you can still keep tabs on her while she sleeps with the Baby Monitor [1] application for iPhone ($5). Simply place your iPhone near your sleeping baby, and if it detects noise it will place a phone call to the number of your choice (like the land line at your best friend's house). You can then listen in for activity from your tot — the super smart program will also detect if your babe picks up the phone.

Sold? Download it from iTunes [2], and check out other great iPhone applications for parents and parents-to-be [3].