The RedBoard Artemis ATP is affectionately called 'All the Pins!' at SparkFun. The Artemis module has 48 GPIO and this board breaks out absolutely every one of them in a familiar Mega like form factor.
The Artemis Module from SparkFun is the world's first open source hardware RF module enabling both voice recognition and BLE. The core of the Artemis module is the Apollo3 by Ambiq. This is an ARM Cortex-M4F (F indicates hardware floating point operations) with BLE 5.0 that runs at less than 1mA. And it can run TensorFlow models.
You can program and use the Artemis Redboard just like you would an Uno or any other Arduino. With 1M flash and 384k RAM you'll have plenty of room for your code. The on-board Artemis module runs at 48MHz with a 96MHz turbo mode available and with Bluetooth to boot.
More information is available on the website of Sparkfun.