I have used a Bluefruit EZ-Link – Bluetooth Serial Link in my latest Master Clock. The clock is wall mounted away from my PC so I have used the Bluefruit EZ-Link to program and read the clock remotely with my PC. I can also read the clock with my Android mobile phone.
Bluefruit EZ-Link – Bluetooth Serial Link & Arduino Programmer: We are excited to add another product to our growing Adafruit Bluefruit line, this time it’s the Bluefruit EZ-Link: the best Bluetooth Serial Link device ever made. Like you, we have purchased all sorts of Bluetooth serial link modules, with high expectations – we just wanted something that worked! But nothing ever did exactly what we wanted: there was always some configuration modes to wade through, and using one of those other modules to reprogram an Arduino is impossible. (read more)
Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, TinyGO, or even use the Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for CircuitPython, MakeCode, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.