The SalesMatik app requires iOS (iPhone Operating System) 10.0 or higher to work successfully on your iPad or iPhone.
To check your iOS version, open the 'Settings':

And then go to 'General' > 'About':

Where you will find the details of your device, including the 'Software Version':

If an update is needed, you can download it in the 'Software Update'-menu in the 'General' settings:


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