This particular pump requires it because its a wearable with no interface. There are still some that have a drip line and cannula, but, I dunno about their interface, they very well may require a phone too. The Omnipod system does come with a "free phone". It's some no-name Motorola that's about twice as thick as a regular phone. I don't really want to carry it, my personal phone, and my work phone, way too much junk. Before smartphones, the pump was the interface, a small screen, a few buttons and AA battery powered. They were OK, but had several downsides. The drip line being the biggest for me, it was always getting caught on stuff.