Good Gear Guide
In Pictures: 25 essential business apps for iPhone...
If you already use Quickbooks for your small business accounting, Quickbooks Mobile will help you streamline your bookkeeping by adding a mobile client to the mix. The mobile app lets you track sales, send out invoices, and see recent payments from your handset.
Cost: Free with an existing Quickbooks subscription, which starts at $12.95/month.
Available on Android too? Yes
In Pictures: 25 essential business apps for iPhone 5