use url reversing

mobile/templates/mobile/index.html

@@ -6,5 +6,5 @@
 
 <p>Hunt blooming trees in your area.</p>
 
-<a class="btn btn-default" id="btn_scan" href="/mobile/scan">Scan a blooming tree</a>
+<a class="btn btn-default" id="btn_scan" href="{% url 'mobile:scan' %}">Scan a blooming tree</a>
 {% endblock %}

mobile/templates/mobile/scanned.html

@@ -7,7 +7,7 @@ tree is blooming.<p>
 
 <p>You may give it a name now</p>
 
-<form action="/mobile/addtree/" method="post">
+<form action="{% url 'mobile:addtree' %}" method="post">
     {% csrf_token %}
     <input type="text" name="name">
     <input type="hidden" name="tree" value="{{ tree.name }}">

mobile/templates/mobile/thankyou.html

@@ -7,6 +7,6 @@
 <p>Does that feel great? It should! You really achieved something in
 your life!</p>
 
-<a class="btn btn-default" href="/mobile">Back to hunting</a>
+<a class="btn btn-default" href="{% url 'mobile:index' %}">Back to hunting</a>
 
 {% endblock %}