fulminator:
Ty for your reply. Sincerely this was the most specific and clear answer in my 1 week ardui o career. Ty.
You are welcome.
fulminator:
I am trying to control a dc motor from old cd rom with an arduino leonardo from my phone. I will be using a simple html page with a javascript script which i will copy on my phone. I have a galaxy mini 2 with android 2.3.
Bear in mind, as I said before, I haven't actually done anything in this regard. I just had been looking it up recently.
I tend to think that is over-kill having to setup html pages, etc. Given bluetooth, you should be able to load a bluetooth control app on the phone, talk directly to the arduino without having to create an html page and then parse the output. It looks like the bluebots app might be what you want.
Here is the page for the bluebots app: https://play.google.com/store/apps/details?id=blue.bots.free.matt&hl=en
Here is a tutorial from hobbyelectronics.co.uk which is evidently selling an Arduino workalike called the magician, and it uses bluebots to control things: Bluebots, Bluetooth, Android and a Magician.
You can get bluetooth adapters for about $15 on ebay.
fulminator:
The reason I was thinking about using a tablet it is because on arduino mirc channel people told me i need a usb host to connect the arduino, but never crossed my mind wireless connection.
My original android phone (LG Optimus T) did not have the capability for creating USB host devices. My new phone (Galaxay S-II Hercules T-mobile) just requires a $10 cable. As I said previously, I've ordered the cable, and I'm awaiting delivery. This is another option, but I don't know the details yet.
fulminator:
My question is: what do you think of this? Is it feasible? Which is thw simplest aproach, bluetooth? What is the optimal choice, wifi?.
The answer is it always depends. If the android and arduino are going to be close by and you don't need to send megabytes of data through the bluetooth connection, I would think bluetooth. The downside is the range you can communicate is not as great as wifi.
If you go wifi, due to the larger range of the radio signals, you will drain the batteries faster on both the phone and arduino (if the arduino is not plugged into the wall). As I said, if you go the wifi route, you likely have to have software to mimic a web server. However, with wifi, you could easily talk to the device via a laptop. You could talk to the device with bluetooth on the laptop, but you would likely have to have some sort of communication program.
The other solutions I mentioned involve wires, which of course are problematical if you can be physically adjacent to the arduino.