When you reopen you app, you should check isSubscribed() and isPendingSubscription, if your query isn’t in either it means the OS cleared the memory of your app as I stated in:
If your query isn’t present in either, it is your responsibility to save the state of your app before the OS terminates it, not the SDK (there’s a ton of info about this online). If the query is present, but the connection is disconnected, you need to make the request by calling open or resubscribing. To learn more about how the OS makes decisions you should read here:
You can also check isSocketEstablished, isConnected, and isConnecting when reopening your app to get the real connection status of LiveQuery.