Any suitable method to assure a user that the app is up to date. It could be a user initiated “Check for Updates Now” button or “Confirm Update Status” button but my favourite is for all updates to be immediately and automatically pushed to apps and devices and a notification bar or message that the app is up to date. In the security times we have now and ahead of us we cannot afford to have any doubt that we are using the latest and most secure version of any app, software or firmware.