The backup and restore method is created by Apple and works the same for all iPhone, iPod touch, and iPad applications.
iTunes backs up your data automatically every time you connect your iPhone, iPod touch, or iPad to your computer. Please note that iTunes will not back up an iPhone, iPod touch, or iPad that is not configured to sync with that computer.
However if you lose your data on the iPhone, iPod touch, or iPad (e.g. by removing an application from your iPhone, iPod touch, or iPad) and connect your iPhone, iPod touch, or iPad again to your computer, iTunes automatically overwrites the existing backup with a new one. Since you just lost your data on the device, this will effectively delete your previous backup from iTunes!
To prevent this, you need to disable automatic syncing for your iPhone, iPod touch, or iPad in iTunes preferences before you connect the iPhone, iPod touch, or iPad again: iTunes > Preferences… > Devices > Prevents iPods, iPhones, and iPads from syncing automatically
If you want to restore from a backup in iTunes respectively re-install without losing your data, you’ll find instructions on this here under: Re-installing Things on iPhone/iPod touch (FAQ).
If you want to keep a history of your iPhone, iPod touch, or iPad backups, you need to backup the entire iTunes library, see: How to back up your media in iTunes. Each of your iTunes backups contains exactly one iPhone, iPod touch, or iPad back from the point the iTunes library backup has been made.