II was using the MyDays app before I started temping. Now I use it to store info before I put it in FF. I still like the app and it let's you store temps! but mostly I keep it because it has 13 months of my info. I like FF because it illustrates your cycle better. I'm still pretty new to it.
Curious why you would still use MyDays just to store data before you put it in FF? Isnt that an extra unneeded step? Pretty sure FF will let you put in data from past charts. So if you wanted to transfer your data from MyDays to FF it might help FF to have that extra info. That is if you want to spend the time doing that because you'll probably have to do it manually.