In early 2018, three new boards were announced (the Xenon, Argon, and Boron). These have an ARM Cortex M4F (based on a Nordic nRF52840 SoC) which also has Bluetooth 5 and NFC. They have 1M of flash and 256K of ram. They run at 64 Mhz. The Argon interests me the most (insofar as these interest me at all) and includes an ESP32 to get Wifi for $15
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