Voice over LTE (VoLTE) was once billed as the future of roaming voice. By carrying calls over 4G LTE’s IP data channels instead of legacy 2G/3G circuits, operators expected lower costs, higher capacity, and HD-quality voice. It promised to simplify infrastructure and align with LTE and 5G’s all-IP design. On paper, VoLTE has lived up to the promise. Last year, 90% of smartphone shipments were VoLTE-enabled, and more than 120 countries offered VoLTE services. The reality, however, is not so smooth. Coverage gaps, under-optimized network environments, and incompatible handsets, are just some of the issues that have cropped up. For example, when a Canadian carrier shut down 3G recently, older OnePlus devices lost all voice capability. It is perhaps time to reframe the way we think of VoLTE. We need to

think of it not as a final destination but as a bridge, or a stepping stone.