diff --git a/meshterm/ui/dashboard_screen.py b/meshterm/ui/dashboard_screen.py
index 3412b7d..a932c1a 100644
--- a/meshterm/ui/dashboard_screen.py
+++ b/meshterm/ui/dashboard_screen.py
@@ -53,6 +53,7 @@ from ..core.events import MeshEvent
 from ..core.models import NODE_TYPE_REPEATER, Observation, utcnow
 from ..core.regions import Scope
 from ..persistence.repository import OBSERVATION_WINDOW
+from ..platforms import Platform, on_platform
 from ..services.monitor_service import ACTIVITY_BUCKET_S, ACTIVITY_BUCKETS
 from .braillechart import axis_chart, axis_chrome, axis_label_w, meter, timeline_rows
 from .packet_viewer import KIND_STYLES, payload_marks
@@ -125,6 +126,24 @@ _GRID_LABEL_W = 9
 #: The screen's title, before any scope atom.
 _TITLE = "Dashboard — mesh overview"
 
+#: What the whole-mesh activity chart counts, as the heading's aside says it. The desktop
+#: adds the chart's unit, ``one minute per dot column``; a font that draws braille solid
+#: (the PicoCalc's, the Cardputer's — :attr:`~meshterm.platforms.Platform.solid_braille`)
+#: has no dots to count, and on 53 columns the words cost the heading its line
+#: (JP, 2026-10-04). The axis under the chart still marks the minutes.
+_ACTIVITY_ASIDE = "every packet heard · one minute per dot column"
+
+
+@on_platform
+def _bind_activity_aside(platform: Platform) -> None:
+    """Bind the activity heading's aside to the platform's braille (runs now and on switch)."""
+    global _ACTIVITY_ASIDE
+    _ACTIVITY_ASIDE = (
+        "every packet heard"
+        if platform.solid_braille
+        else "every packet heard · one minute per dot column"
+    )
+
 
 class _ScopeDigest(NamedTuple):
     """One scope view's numbers over the window, in the shapes the sections draw.
@@ -429,11 +448,7 @@ class DashboardScreen(Screen):
         heading = Text("Activity", style="accent")
         # A narrowed view spends the aside on what it counts, which the reader has to be
         # told; the minute per column is on the axis beneath either way.
-        what = (
-            "floods in this scope · last 2 h"
-            if self._scope
-            else "every packet heard · one minute per dot column"
-        )
+        what = "floods in this scope · last 2 h" if self._scope else _ACTIVITY_ASIDE
         heading.append(f"  ·  {what}", style="muted")
         # Buckets seeded from a previous session's stored history draw grey; only
         # what this session heard itself pulses green.
diff --git a/tests/test_dashboard.py b/tests/test_dashboard.py
index b703a15..52d99c5 100644
--- a/tests/test_dashboard.py
+++ b/tests/test_dashboard.py
@@ -89,6 +89,24 @@ def test_dashboard_renders_all_three_sections() -> None:
     assert "advert" in body and "Alice" in body  # traffic class + the busiest node
 
 
+def test_the_activity_aside_names_dot_columns_only_where_braille_has_dots() -> None:
+    """The handhelds draw braille solid, so the heading drops ``one minute per dot column``.
+
+    There are no dots there to count, and on 53 columns the words cost the heading its
+    line. The desktop keeps them; both keep what the chart counts.
+    """
+    from meshterm.platforms import PICOCALC, REGULAR, set_platform
+
+    def heading(width: int) -> str:
+        body = _plain(_screen(histogram=[1] * ACTIVITY_BUCKETS).render_body(width))
+        return next(line for line in body.splitlines() if "Activity" in line)
+
+    set_platform(PICOCALC)
+    assert heading(53).strip() == "Activity  ·  every packet heard"
+    set_platform(REGULAR)
+    assert heading(72).strip() == "Activity  ·  every packet heard · one minute per dot column"
+
+
 def test_dashboard_activity_chart_reads_newest_right_with_mirrored_scale() -> None:
     """'now' anchors the right edge and the scale marks mirror on both gutters.