Do all the major platforms support bluetooth now?

I’m trying to do a simple project where I give my mobile device or computer more physical buttons. This is for various purposes. I’m trying to find the simplest way to do this. My first idea was to create an arduino project and pretend to be a keyboard. Then my computer can listen for the key events and respond. if I can do this then I should be able to be able to talk to OSX, Windows, IOS and Android because they all support keyboards.

As I was researching it occured to me that it doesn’t have to be a keyboard, it just has to be able to make connections to a bluetooth device and then it can send key events, correct? I would just need to be able to pair the device and then be able to send key codes to the operating system. IIUC OSX, Windows, IOS and Android all can search and connect to bluetooth but will I still be able to send keyboard events?

So, next I found guides on creating Human Interface Devices or HID devices. So if all I need is bluetooth support then I simply need a bluetooth getting started project.

What I want is very simple. I want to have a low powered, battery powered, bluetooth device that can connect to osx, android, ios, and windows. It will have maybe 6 buttons. Those buttons will send keyboard codes 1, 2, 3, 4, 5, 6 and so on.

One more thing, If I get a Arduino and so on, I’ve seen they have screens that can be attached! What does this mean? Can I open a web page and in full screen? I can then build my app with that? Or should I connect to existing computers?

I haven’t picked a platform yet but both Arduino, Rasberry Pi and SparkFun Qwik look very capable for my needs. The only issue with SparkFun Qwik is that it seems new and I don’t know if it has all the help resources that the others might have. I don’t know.

If I can easily connect to the major platforms through blue tooth and what I’ve described above is correct, what do I need to buy? Thank you so much!

I think you should proceed with Raspberry Pi. You can choose either Raspberry Pi 4 or Pico. Here is a project which is quite similar with what you want to do: https://www.youtube.com/watch?v=__QZQEOG6tA

Simplest way to do this would be to skip bluetooth entirely and use something like a pro micro.

https://www.sparkfun.com/products/15795

That along with the arduino keyboard/ mouse library will make the pro micro appear to your computer as a USB keyboard.

https://www.arduino.cc/reference/en/lan … /keyboard/

With a bit of code you can connect buttons to the pro micro and pressing them will cause them to show up as key presses to your computer. Some example code can be found in the library, some more advanced code can be found below.

https://learn.sparkfun.com/tutorials/ke … iic-keypad