Optional
checkIt's the control method - it should check the response and return boolean If returns true - everything is ok, no need to resubscribe If returns false - something is not ok, the IrisManager will try to reconnect with the new value from .get() method Basically it is needed to clear the seq_id cache
Strategy for getting the seq_id for the iris subscription. It differs for web and android, because the current seq_id is fetched with http request.