Return device dict
    For example:
    {
        "1002038889199992134bad1234112312": "Tony's iPhone"
    }

def devices():
    """
    Return device dict
    For example:
    {
        "1002038889199992134bad1234112312": "Tony's iPhone"
    }
    """
    udids = [udid.strip() for udid in idevice('_id', '-l').splitlines() if udid.strip()]
    return {udid: idevice('name', '-u', udid).decode('utf-8').strip() for udid in udids}