Love the Web Access feature in Express Invoice 
!
Everything scales excellent on an iPhone, no complaints .
I do have a 2x suggestions however:
Please can you add a "call-from-link" for both the primary and alternative phone numbers for my iPhone under Customers.
e.g http://www.my-iphone.com/assets/images/hints-tips/call-from-link.jpg
Also is it possible you could add a "date modified" column so I can sort by recent customers?
Very impressed so far!