diff --git a/core/constants.py b/core/constants.py
index 8d51f37..a66d916 100644
--- a/core/constants.py
+++ b/core/constants.py
@@ -39,11 +39,27 @@ ACTIVITIES = [
     Activity(
         name="EME",
         comment_names=[],
-        description="Moonbounce",
+        description="Earth-Moon-Earth (Moonbounce)",
         sig_type=ActivityType.TRADITIONAL,
         icon="fa-moon",
         refs_globally_unique=False,
     ),
+    Activity(
+        name="/AM",
+        comment_names=[],
+        description="Aeronautical Mobile",
+        sig_type=ActivityType.TRADITIONAL,
+        icon="fa-plane",
+        refs_globally_unique=False,
+    ),
+    Activity(
+        name="/MM",
+        comment_names=[],
+        description="Maritime Mobile",
+        sig_type=ActivityType.TRADITIONAL,
+        icon="fa-sailboat",
+        refs_globally_unique=False,
+    ),
     Activity(
         name="QRP",
         comment_names=["QRP"],
diff --git a/data/spot.py b/data/spot.py
index 78a52d3..f482afb 100644
--- a/data/spot.py
+++ b/data/spot.py
@@ -384,6 +384,13 @@ class Spot:
             if self.propagation_mode == "Earth-Moon-Earth" and not self.sig:
                 self.sig = "EME"
 
+            # Set activities based on the DX callsign suffix
+            if self.dx_call and not self.sig:
+                if self.dx_call.upper().endswith("/AM"):
+                    self.sig = "/AM"
+                elif self.dx_call.upper().endswith("/MM"):
+                    self.sig = "/MM"
+
             # Parse "de_grid -> dx_grid" structures from the comment
             if self.comment:
                 grid_mode_grid_match = re.search(
diff --git a/static/apidocs/openapi.yml b/static/apidocs/openapi.yml
index b65f878..ffea99f 100644
--- a/static/apidocs/openapi.yml
+++ b/static/apidocs/openapi.yml
@@ -19,6 +19,7 @@ info:
     
     * Renamed AMSAT SIG to "Satellite" as AMSAT is a specific organisation not just a general term for satellite QSOs
     * Removed `alert_type` from alert data. Contest, DXpedition and Satellite alerts now give those values in `sig` instead, alongside the existing outdoor activity programmes. Teeeeechnically a breaking change but AlertType is so new I doubt anyone is using it yet, so slipped this one in anyway. Sorry :)
+    * Added QRP, RaDAR Rally, /AM and /MM activities
 
     ### 2.1
     
@@ -884,6 +885,13 @@ components:
     ActivityName:
       type: string
       enum:
+        - Contest
+        - DXpedition
+        - Satellite
+        - EME
+        - /AM
+        - /MM
+        - QRP
         - POTA
         - SOTA
         - WWFF
diff --git a/templates/about.html b/templates/about.html
index 06a6d06..6c24c8c 100644
--- a/templates/about.html
+++ b/templates/about.html
@@ -14,9 +14,8 @@
         source, freeing developers from needing to know how each individual data source presents its data.</p>
     <p>Spothole itself is also open source, Public Domain licenced code that anyone can take and modify. <a
             href="https://git.ianrenton.com/ian/spothole/">The source code is here</a>.</p>
-    <p>The software was written by <a href="https://ianrenton.com">Ian Renton, MØTRT</a> and other contributors. Full
-        details are available in the <a href="https://git.ianrenton.com/ian/spothole/src/branch/main/README.md">README
-            file</a>.</p>
+    <p>The software was written by <a href="https://ianrenton.com">Ian Renton, MØTRT</a> with code contributions by
+        Steven, M1SDH. The full list of thanks due to others can be found at the bottom of this page.</p>
     <p>This server is running Spothole version {{software_version}}.</p>
     <h2 class="mt-4 mb-4">Using Spothole</h2>
     <p>There are a number of different ways to use Spothole, depending on what you want to do with it and your level of