Contractions

Stacey • 27 with a 6 year old and a 2 year old with another on the way(my last) :)
Is there a good app for recording contractions and how to record them? I'm having a lot of braxton hicks and with them getting stronger, I'm thinking a more accurate recording of them could help with when I should go to hospital and if they are labour ones or not. I have my midwives on call to double check before I leave though.