Good Gear Guide
In Pictures: 20 essential business apps for iPhone...
Developer: AgreeYa Mobility
Cost: $2.99/month for the Lite version; $3.99/month for the Pro version
Available on Android too? Yes
Onvelop is an iPad unified collaboration and communication app that gives you enterprise mobility and BYOD capabilities through secure access to Office 365, SharePoint and Lync. Using licensed Microsoft protocols to enable mobile access to enterprise server software, the app provides employees with the flexibility they need to work and communicate with their own iPhones and iPads.
In Pictures: 20 essential business apps for iPhone and iPad