@Nullable
    @WorkerThread
    public static String createBookmarkList(final String name, final Geocache geocache) {
        final ObjectNode jo = new ObjectNode(JsonUtils.factory).put("name", name);
        jo.putObject("type").put("code", "bm");

        try {
            final Parameters headers = new Parameters(HEADER_VERIFICATION_TOKEN, getRequestVerificationToken(geocache));
            final String result = Network.getResponseData(Network.postJsonRequest("https://www.geocaching.com/api/proxy/web/v1/lists", headers, jo));

            if (StringUtils.isBlank(result)) {
                Log.e("GCParser.createBookmarkList: No response from server");
                return null;
            }

            final String guid = JsonUtils.reader.readTree(result).get("referenceCode").asText();

            if (StringUtils.isBlank(guid)) {
                Log.e("GCParser.createBookmarkList: Malformed result");
                return null;
            }

            return guid;

        } catch (final Exception ignored) {
            Log.e("GCParser.createBookmarkList: Error while creating new bookmark list");
            return null;
        }
    }
Creates a new bookmark list. Shouldn't be called on main thread!

@return guid of the new list.
main/src/main/java/cgeo/geocaching/connector/gc/GCParser.java