Have any of you tried those heart beat apps to hear your baby's heart beat in between doctor's appointments? I'm 24 weeks, my first time being pregnant, and I haven't felt a lot (or any) movement and I'm starting to get concerned. It has been 6 weeks since my last doctor's appointment because she has been on vacation and I was really looking forward to my appointment which was supposed to be today. However they canceled so now I have to wait another week and a half to get some peace of mind. So I was wondering if anyone has tried an app to listen to the heart beat and was successful? If so, what would you recommend? Thank you!!