What the 100 MHz Cortex-M4 core buys you
That core includes a single-precision FPU and a DSP instruction set, so control loops and sensor fusion algorithms that would eat an M3's cycles run in fewer iterations.
Package and thermal pad — layout checklist
The part ships in a 48-UFQFN with an exposed pad (7x7 mm body). That pad is the main thermal path to the board — without a via array under it, junction temperature climbs fast above 200 mA continuous. The 36 general-purpose I/Os route out on two sides, so a two-layer board is possible if the decoupling caps sit close to the supply pins. The UFQFPN land pattern needs a solder-paste stencil aperture that matches the exposed pad area; a 50 % coverage keeps voids manageable.
Peripherals and connectivity — what is on the bus
On the peripheral side you get I²C, SPI, UART/USART, USB OTG, I²S, and SDIO — enough to talk to a sensor array, log to an SD card, and stream audio over USB in a single chip. The 10-channel 12-bit ADC samples at up to 2.4 MSps, which is adequate for current-sense feedback in a 20 kHz current loop but not for high-speed data acquisition.