A flow control mechanism, express virtual channels (EVCs), was recently presented to close the gap between packet-switched networks and the ideal interconnection through virtually bypass intermediate routers. Currently, EVCs paths are inserted regularly. This paper proposes a novel methodology to insert EVCs in an application-specific way (AS-EVC) by exploiting communication characteristics of applications, with the main objective to reduce more NoCs power. Additionally, accurate evaluations were performed based on low-level, synthesizable models. The results on a range of synthetic and real workloads show that up to 23.49% router power is saved by AS-EVC, compared to the baseline design. Also, AS-EVC outperforms static EVCs under all traffics, with 57.14% more power is saved on average for tested Minne-SPEC benchmarks.