If you're trying to connect to your Deeper Sonar via the FishDeeper app, but getting the "Your Deeper Sonar is already connected to the Deeper Smart Sonar app" error, there could be 2 possible reasons for that:
1. Android and iOS devices: This can happen if you are using the old Deeper app (Deeper Smart Sonar app), and it's already connected to the Deeper Sonar. This will prevent the FishDeeper app from connecting.
We strongly recommend deleting the Deeper Smart Sonar app, because it's an outdated app that is no longer supported by Deeper company. Instead, use the FishDeeper app which is the current and supported app. You can download it on Google Play or Appstore.
2. iOS devices only: This can happen if you're using a Navionics and FishDeeper app at the same time. Navionics app tries to access certain connection events of the smartphone, which are also used by the FishDeeper app. This prevents the FishDeeper app from successfully connecting to the Deeper Sonar.
Unfortunately there is no way to bypass this. We recommend not to use the Navionics and FishDeeper app at the same time.