Updating to a new version
To make sure you're protected by the latest security updates, Google Chrome can automatically update when a new version of the browser is available on your device.With these updates, you might sometimes notice that your browser looks different.If an update is available your device then you will be asked whether you wish to install it.
Note: You device may require a Wi-Fi connection to search for an update.
We also recommend downloading the software over Wi-Fi because the file size can be large.
If your device is running anything lower than Jelly Bean, unless you have simply never updated its software it's very unlikely that an update for Marshmallow or Kit Kat will be available for it (the manufacturer doesn't appear to support this device any longer).
As a precautionary measure it's good practice to back up your data such as contacts and photos.
The upgrade should not affect your data but there are no guarantees. On most Android devices this can be done via the app menu or notification bar.