Under normal circumstances, the business contacts, emails and documents critical to your business remain safely in your i Phone when you upgrade it to a new version of i OS.Apple designs the upgrade process to affect only the components of i OS itself, including the operating software and essential apps, not your purchased apps or your files.However, if the i Phone is jailbroken or if it cannot complete the update normally, you can lose files temporarily.ITunes can detect when a new version of i OS is available for your i Phone. Now i need to upgrade it to the latest OS version, WITHOUT deleting any data.I have not tried to update my phone contacts in the last few years fearing it would delete the data. Upgrades aren't supposed to delete data, but you can't really test if your data is corrupt, so you need to perform and test your backup if you fear losing data.
The program inspects your software when you click the "Check for Update" button and compares it with Apple's latest release.
If i Tunes finds new software, you can update your i Phone.