I backed the Kickstarter Particle Electron project in 2014. Particle is an IoT Platform that contains everything you need to power your IoT product, from the device to cloud. The Kickstarter project version came with a number of sensors. It is based on the STM32F205 ARM Cortex M3 microcontroller with 1MB Flash and 128K RAM
Docs on The Electron kit . It is a very fast and economical way to build, test and deploy IoT projects.