OK, while I'm very annoyed at having to buy the iOS app a THIRD time and only a couple of months after the most recent purchase, the kicker was that it just won't work!
1. After buying it and installing it on my iPad3 (where version 3.7.2 is already installed AND working), I launched it and was told I had to create a Master Password. Hello, why didn't just pull the one from 3.7.2?
2. So I "created" using the same one from 3.7.2. Let's call it "1234". Next I was asked to import my 1P keychain which I had to do via Dropbox because WiFi hasn't been enabled in version 4 yet.
3. After starting the Dropbox connection, I was back at 1P4 where 1P4 asked me to enter my Master Password again. So I enter "1234" and 1P4 says, INVALID!
4. After several tries with the same result (I even tried the master password for 1P3.8 on my iMac), I deleted 1P4 from my iPad3, and from iTunes. 1P3.7.2 works fine so I don't need 1P4.
Cons: I'm out $8
Pros: I gave 1P4 a negative rating in the iTunes Store, and at my Mac User Group meeting, I reccommended NOT using it, but to just stay with 1P3.7.2 instead.
(Hey, at least I'm not talking about getting an attorney involved, as some others are.)