[Answer]-Change zinnia app name to Blog Django admin

well you can try like:

class Zinnia(models.Model):
        ....
    class Meta:
        app_label = 'Blog'

update:

well, from django source code: https://github.com/django/django/blob/731f313d604a6cc141f36d8a1ba9a75790c70154/django/contrib/admin/templates/admin/index.html#L15

You can simply override django admin’s index page to change app name in adminsite.(check: how to override admin template). Do this (templates/admin/index.html):

{% if app_list %}
    {% for app in app_list %}
        <div class="app-{{ app.app_label }} module">
        <table>
        <caption>
            {% if app.name == 'Zinnia' %}
            <a href="{{ app.app_url }}" class="section" title="{% blocktrans with name=app.name %}Models in the Blog application{% endblocktrans %}"> Blog </a>
        </caption>
        {% for model in app.models %}

 ....