In order to test the sketch described on the previous page, you can use a free UART application from Nordic Semiconductors
that's available in Apple's app store for recent iOS devices or Android's Play Store for Android 4.3 or higher devices.
Be sure to use the 2.0 version of the app on Android. The earlier (non 2.0) version is based on a proprietary BLE stack for certain Samsung devices, which was created before Google added official support for BLE in Android 4.3.
Once the device starts advertising, you can open the nRFUART 2.0 application, and you should be able to connect to the 'UART' device, similar to the screenshot below:
Once you're connected, you can click on the 'send' textbox at the bottom, and any data you send out should show up in the Serial Monitor, and also get echoed back to the Android application, as seen below:
You will need an Android device running Android 4.3 or higher with BLE support to use this application. Nexus 4, Nexus 5 and Nexus 10 devices running the latest version of Android can all use this application, but other devices will need to be verified for BLE support.
iOS: nRF UART
If you are using a BLE-enabled iOS device (recent iPhones, iPod Touch models, iPads, etc.), you can also test this on iOS.
- Download nRF UART application from Apple's App Store.
- Load the 'callbackEcho' sketch onto your Arduino (File > Examples > Adafruit_nRF8001 > callbackEcho)
- Once the sketch is running, open up the Serial Monitor at 9600 baud.
You should be able to connect to the board using the 'Connect' button in the iOS application now, and send and receive text via the textbox at the bottom of the app: