An eSIM is a digital SIM card that is embedded into your phone. Buying an eSIM in Japan offers several benefits, including convenience and flexibility. With an eSIM, you can activate your phone service without needing a physical SIM card, which can be especially useful for travelers who may need to switch carriers or obtain service in multiple countries. Additionally, eSIM providers may offer more competitive rates and packages compared to traditional SIM cards, which could potentially save you money on your phone service. Finally, using an eSIM is environmentally friendly since it eliminates the need for a physical SIM card, reducing waste and promoting sustainability.