I too am having a similar problem. I recently joined and input my collection via the web site without any issues. Then when I signed in through the app on my Iphone 5 and synched my collection showed up but there were a few strange entries. At the top on my humidor there were three blank entries where there was a number of cigars listed as one but no other information. If i go in to exit these entries it lists the name as "(null) (null)" price as $0.00 and number as 1. It appears that all of my cigars showed up but with three extra blank entries. I do not see these entries in the web site.
I fixed those entries as well as edited a few others and tried to synch and it overrode the changes I made on my iPhone so I was back to the same listings in my humidor that I started with, including the 3 empty entries. I tried synching both ways, just to make sure I didn't misunderstand the overwrite all function.
I think this could be a great tool, but it doesn't appear that it is synching when I make changes to my humidor on my iPhone via the app. Please let me know if there is something I'm missing as I haven't gotten any timeout errors, etc. thanks for your help!