pfodApp (www.pfod.com.au) connects from Android phones to 101 via BLE (pfodApp also supports Bluetooth, WiFi and SMS connections to other boards)
I test using two phones Asus Zenphone 5 (ASUS_T00J) running Android 4.4.2
and Nexus P6 running Android 6.0.1
Both of these work fine.
BLE support was introduced in Android V4.2 but that version and V4.3 were very buggy. V4.4 improved the BLE support
Previously I had problems with the connection dropping out after 5mins but Arduino board firmware/libary updates seem to have fixed that.
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a free pfodDesignerV2 app is available that will let you design pfodApp menus on your Android phone and then generate the Arduino code that reproduces them. see http://www.forward.com.au/pfod/pfodDesigner/index.html for detailed examples