Update for everyone else: still doesn't work. Thought it could be because I use a smaller-screened iPhone, so tried w/ a friends and it wouldn't work there, either. Same old, same old, the "Whoops, something needs to be fixed" followed shortly thereafter with, "We can't deposit this check. Try depositing another check."
 
All checks we receive from clients are printed business checks, all less than $600. Not a single check has been successful so we remain trapped having to deposit into another bank and then transfer into QuickBooks Checking / Green Dot.
 
Unless Intuit can get its act together, come summer, we're definitely going back to our old online bank... since have to deposit checks there, anyway, and closing our bank account with QuickBooks.
 
Warning to anyone considering: do not sign up for QuickBooks  / Green Dot Checking. Not only is the support terrible - all they do is repeat the same thing over and over again no matter how may times you tell them you've already done them - not only is it incapable of depositing checks - which given it's an online bank is, well, basically one of the most important things a bank should be able to do - but it doesn't even really integrate with QuickBooks very well, either, so you may as well just stay with a bank that knows how to be a bank. We only moved b/c of the (back then) 4% envelope interest, which is quickly decreasing. Moreover, even what interest it does earn doesn't matter as much anyway now that QuickBooks also takes out all payroll taxes on payday rather than quarterly like it had always been previously... and then of course, they are so kind to turn right around offer to loan that money back to us... one hopes someone over there is at least slightly embarrassed, but I doubt it.