This paper presents a hybrid method, validated through a series of experiments for balancing of rigid and flexible rotors at a constant rotational speed. Unlike existing balancing methods, this hybrid method combines the benefits of the 4-runs method and the Influence Coefficient (IC) method without requiring a response phase measurements to estimate three correction weights so as to minimise rotor balancing errors. The proposed method requires three trial runs without phase measurements to localise the position of unbalance using the centroid concept. Then, calculating the phase angles of each trial run to apply, three times, the IC balancing method. Finally, estimating the overall corrective weight from these three correction weights. A comparative study was used to verify the reliability of this hybrid method as a contrast test. Additionally, two experimental cases were designed to evaluate the method in two different operating environments. Experimental analyses show that the proposed method presents acceptable results, despite the use of a modest instrument such as the smartphone to acquire the vibration signal of the unbalanced rotor. In this context, this paper highlights the oppor- tunities behind smartphones, which can be a reliable tool to perform professional operations such as field balancing for rotating machinery.