I haven't run it yet and from what I've read on quickbooks website the mobile apps apear pretty limited.
I do a lot of purchases of supplies and stuff with a company debit card and the QBOL and mobile apps won't let you record stuff like that last time I looked. That was the deal breaker for us.
As for the Online version, an awful lot of money each year, (more than buying a new version of QB for the PC) and seemingly less functionality
Needless to say, we're still desktop bound.