def make_droid_skeleton_bbm(method, build, device, variant='common'):
    """
    Make an Android autoloader/hash URL, on the BB Mobile site.

    :param method: None for regular OS links, "sha256/512" for SHA256 or 512 hash.
    :type method: str

    :param build: Build to check, 3 letters + 3 numbers.
    :type build: str

    :param device: Device to check.
    :type device: str

    :param variant: Autoloader variant. Default is "common".
    :type variant: str
    """
    devices = {'KEYone': 'qc8953', 'Motion': 'qc8953krypton', 'KEY2': 'sdm660'}
    base = 'bbry_{2}_autoloader_user-{0}-{1}'.format(variant, build.upper(),
        devices[device])
    if method is None:
        skel = 'http://54.247.87.13/softwareupgrade/BBM/{0}.zip'.format(base)
    else:
        skel = 'http://54.247.87.13/softwareupgrade/BBM/{0}.{1}sum'.format(base
            , method.lower())
    return skel
