If you are experiencing connection problems, timer disruptions or data loss, please update your phone operating system if possible (and you haven't already done so) and make sure you have the 4.2 version of the Oral-B App. Upgrading to Android 7.1.1 (currently rolling out) and iOS 10.3.1 (now available), should resolve this for most users.
Unfortunately there are certain phones that may continue to experience Bluetooth connection issues with the Oral-B App 4.2 and Android 7.0 and up releases. We hope this will be resolved with a future bug fix for Android 7, and we are working with Google and affected suppliers. Ultimately, though, it's up to them to determine when Android upgrades will launch and when phone upgrades are rolled out. We appreciate your patience.
If you have Android and you aren't able to download 7.1.1 yet, please keep an eye out for this as in most cases this works in solving the issues.