For sale in 2012 at a price of only $35, the Raspberry Pi revolutionized the world of low-cost Linux-based developer platforms. Since then the vendor, Adafruit Industries, has sold more than four million, a figure that displays the success of the project.

The Raspberry Pi Foundation recently presented the Raspberry Pi A+ Model, an updated version of the platform over the previous generation. The A+ model now comes with smaller and cheaper price tag: $20, down from $35. The A+ is described as a “small, energy-efficient and crazy-affordable” way to get into computing, or to hack products and create new engineering projects for developers and coders with more experience.

Most of the basic specs remain the same: same Broadcom BC2835 processor, same trends as the B+ in terms of layout and design. The new Raspberry Pi A+ changes include more General-Purpose Input/Output pins (GPIO), it possesses a larger 40 pin GPIO header; SD card socket has been replaced with a much nicer push-push micro SD version and the audio circuit is enhanced for better audio output. All these enhancements are done in the significantly smaller model now (65mm in length, versus 86mm for the Model A), which also consumes less power.

“We want to get them into the hands of children so they can learn about computers and programming,” said James Adams, director of hardware engineering. “Parents might not want to let children play about on computers, but this gives them access to technology at an affordable price.”

The A+ is now smaller than a credit card and weighs only 23g (against 31g for A and 41g for B+). The PCB slot HAT includes additional fittings, and the model replaces the old SD slot with a micro SD slot. On the downside, the new version has half the RAM, no Ethernet, and only one USB port instead of four. Unlike B/B+ versions, there is also no network port on the Raspberry Pi A+.

The bold history of the Raspberry Pi Foundation

The foundation has sold more than 4 million Raspberry Pi computers, which have been used to build educational computers, economic, media servers and more. Hackers have built a secure, personal-cloud OS called arks with easy setup and a GUI. The Pi has been configured to combine with the privacy-network onion router Tor, which thus allows homeowners to easily connect it to their own network. The Raspberry Pi Compute Module is also being used in the field of industrial automation.

The Raspberry Pi A+ model is immediately available; but the model B+ will remain in production for as long as demand continues. You can buy A+ from Farnell in the UK, and MCM in the US.