Raspberry Pi - the hacker friendly, cheap mini-computer started a whole new niche of users tinkering with these easily accessible hardware and open-source software to create awesome projects. There are now a plethora of such ARM development boards from single-core, dual-core to quad-code varieties having all sorts of ARM CPU options like Rockchip, i.MX Freescale, Samsung Exynos etc. with various RAM, connectivity and falsh storage options.
Radxa Rock is the newest entry into this arena and seems to pack a solid punch of hardware and software power, powered by Quad core ARM Cortex-A9 processor the board manages to clock as high as 1.6Ghz and as low as 324Mhz, balancing between performance and power saving. The single-board computer uses RK3188 as the quad-core CPU and comes with 2GB DDR3 @ 800Mhz, 8GB Nand Flash, Micro-SD SDXC up to 128GB, Mali400-mp4@533Mhz GPU with OpenGL ES 2.0 support, video output via HDMI 1.4 up to 1080p@60hz, integrated Bluetooth 4.0, WiFi with external antenna, LAN, RTC, IR, USB OTG, S/PDIF, headphone jack, built-in microphone and 80 pins including GPIO, I2C, SPI, Line in, USB 2.0, PWM, ADC, LCD, etc. allowing users to easily connect rock with breadboard or other sensor boards.