28% without interaction is a lot.
If possible, send me your project by email (support@infinity-code.com), I will check why this is happening.
To make it clear:
I don't need your working project.
I need any temporary project where the problem manifests itself.

A long time ago there was a directive for Android, but I don't remember why I removed it.
Most likely there was some problem with using the mouse on android devices.
I added this directive again and in the next version it will contain the directive for Android.

You are using UI Image Control or UI Raw Image Control, right?
Consider using a tileset. It's much faster and uses less memory.
Yes, a Raycast is needed here, but it is needed once, and the map can make several raycasts per frame.
Thanks for showing me this.
I will try to optimize this behavior.

HitTest() calls EventSystem.RaycastAll() which is VERY expensive.

############

protected void Update()
    {
        if (OnUpdateBefore != null) OnUpdateBefore();

        BeforeUpdate();
        _screenRect = GetRect();

        int touchCount = GetTouchCount();

        if (touchCount != lastTouchCount)
        {
            if (allowTouchZoom)
            {
                if (touchCount == 1) OnMapBasePress();
                else if (touchCount == 0) OnMapBaseRelease();
            }

            if (lastTouchCount == 0) UpdateLastPosition();
        }

        if (isMapDrag && !smoothZoomStarted) UpdatePosition();

        if (allowZoom)
        {
            UpdateZoom();
            UpdateGestureZoom(touchCount);
        }

        lastTouchCount = touchCount;

        if (dragMarker != null) DragMarker();
        else if (HitTest())
        {
            map.tooltipDrawer.ShowMarkersTooltip(GetInputPosition());
        }
        else
        {
            OnlineMapsTooltipDrawerBase.tooltip = string.Empty;
            OnlineMapsTooltipDrawerBase.tooltipMarker = null;
        }
        AfterUpdate();

        if (OnUpdateAfter != null) OnUpdateAfter();

        UpdateLastPosition();
    }

########

I just thought I'd ask if there's an 'offical' way of getting it to go to sleep when it's idle before I start hacking away.

Of course, I'm not completely oblivious to the idea that I might just be doing something stupid.

Version is 3.7.6.2 and host is Unity 2020.1.13f1

Many thanks.

Rob.

Edit -

Should this also include Android ?

/// <summary>
    /// Updates the map zoom for mouse wheel.
    /// </summary>
    protected void UpdateZoom()
    {
#if UNITY_IOS && !UNITY_EDITOR
        return;
#endif