I used Ovia fertility tracker, and got pregnant during the second month of using it, so then switched over to Ovia pregnancy. I have two other pregnancy apps, but Ovia is my favorite because it provides new updates and tidbits all throughout the day. The info is also totally customized to you and your symptoms. The interface is very cheerful, cute, and encouraging. I highly recommend!
BabyAdamsJan2015 about Ovia Pregnancy & Baby Tracker, v3.0.5