I see their board uses a daughter board from Phytec, a German company too. This is based on very high performance NXP MCU, the i.MX 6UL, with additional external DDR RAM.

It's a $212 SBC. They've got more L2 cache than most microcontrollers have Flash memory.The fact that it's got an L2 cache at all, much less external LPDDR3 DRAM, is a bit ridiculous. In most parameters - cost, RAM, frequency, storage, power consumption - it's approximately 2 orders of magnitude beyond the specifications of a normal microcontroller.

NPX calls[1] it an application processor, and is based on a Cortex-A7, not a Cortex-M series microcontroller processor.

That said these nomenclatures are a bit fuzzy these days.

[1]: https://www.nxp.com/products/i.MX6UL