SoftPOS
An ordinary smartphone accepting contactless card payments through its own NFC antenna, no extra card reader required.
For a long time, reading a payment card required a certified terminal with its own secure chip. iZettle and its peers got around this with a small dongle paired to the phone. Once phones gained NFC and sufficiently trustworthy execution environments, the dongle became redundant, at least for contactless cards. The PCI Security Standards Council published the CPoC standard in 2019 and the broader MPoC in 2022, letting software on a stock phone be certified.
Android got there first. Apple opened up the NFC chip for the purpose with Tap to Pay on iPhone, announced in February 2022. For hairdressers, market stalls and plumbers it means taking cards on the phone they already own. PIN entry on a touchscreen was long the last obstacle, and remains the most argued-over part.