This paper presents a mechanism for steering connections to different mobile networks for UAV-based reliable communications. This connection steering mechanism works by selecting the best Radio Signal Strength Indicator (RSSI) quality among the available networks in order to ensure the highest availability. In this work, we developed a test-bed to evaluate the performance of the steering mechanism. In addition, to mimic the mobility of UAVs, we analyze our work by applying Discrete Time Markov Chain (DTMC) to evaluate the performance of the testbed results. The results obtained from our analysis and testbed-based evaluation show the efficiency of the proposed connection steering mechanism. These results demonstrate the efficiency of the proposed connection steering mechanism in terms of data packet transmission rate and energy consumption saving.