eSIMs, being digital, allow you to install multiple plans on your phone without the physical limitation of a sim card. The number of eSIMs you can store and activate is device-specific. For iPhones, you can install five or more eSIMs on an iOS device, with two being active simultaneously. Your iPhone can be set up with two phone numbers for voice calls and messages, using one mobile data network at a time. However, this can vary based on the iPhone model, location, and network provider. For Android devices like Samsung, Google, Huawei, etc., the number of installable and active eSIMs varies. Typically, you can have five to seven eSIMs installed, with one active at a time.