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