Two iPhones, One Phone Number
With iPhone Handoff you can have two iPhones on one phone number and pick which one is the active phone. Going to the gym, I'd bring the smaller phone and switch my number to it, and the Duo at home turns into basically an iPad: iMessage and Wi-Fi calling still work, just no cell tower. As of Oct 10, T-Mobile is the only US carrier doing it ($5 a month), and Apple says Verizon gets it before the end of 2026.
Source: https://www.slashgear.com/2277371/which-phone-carriers-support-iphone-handoff/
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