StaggeredGrid

MainPage-snippet.xaml

        <ItemsControl x:Name="items" Grid.RowSpan="3" ItemsSource="{x:Bind Data}" Background="LightGray">
            <ItemsControl.ItemsPanel>
                <ItemsPanelTemplate>
                    <local:StaggeredGridPanel />
                </ItemsPanelTemplate>
            </ItemsControl.ItemsPanel>
            <ItemsControl.ItemTemplate>
                <DataTemplate>
                    <Border Margin="5" Background="{Binding Brush}" Height="{Binding Height}">
                        <TextBlock Text="{Binding Name}" HorizontalAlignment="Center" VerticalAlignment="Center" />
                    </Border>
                </DataTemplate>
            </ItemsControl.ItemTemplate>
        </ItemsControl>

MainPage-snippet.xaml.cs

  public class TestData
        {
            public string Name { get; set; }
            public SolidColorBrush Brush { get; set; }
            public double Height { get; set; }
        }
        public List<TestData> Data
        {
            get
            {
                Random r = new Random();
                var d = new List<TestData>();
                for (int i = 0; i < 30; i++)
                {
                      d.Add(new TestData() { Name = (i+1).ToString(), Brush = new SolidColorBrush(Windows.UI.Color.FromArgb(255,(byte)(255d/30*i),0, (byte)(255 - (255d / 30 * i)))), Height = r.Next(50, 200) });
                }
                return d;
            }
        }

StaggeredGridPanel.cs

    public class StaggeredGridPanel : Panel
    {
        protected override Size ArrangeOverride(Size finalSize)
        {
            int cols = (int)Math.Floor(finalSize.Width / MaxColumnWidth);
            var w = finalSize.Width / cols;
            List<double> colHeight = new List<double>(cols);
            for (int i = 0; i < cols; i++)
                colHeight.Add(0);
            foreach (var child in Children)
            {
                //use the shortest column
                var col = colHeight.IndexOf(colHeight.Min());
                double x = w * col;
                double y = colHeight[col];
                child.Arrange(new Rect(x, y, w, child.DesiredSize.Height));
                colHeight[col] += child.DesiredSize.Height;
            }
            return new Size(finalSize.Width, colHeight.Max());
        }

        protected override Size MeasureOverride(Size availableSize)
        {
            int cols = (int)Math.Floor(availableSize.Width / MaxColumnWidth);
            var w = availableSize.Width / cols;
            availableSize = new Size(w, availableSize.Height);
            List<double> colHeight = new List<double>(cols);
            for (int i = 0; i < cols; i++)
                colHeight.Add(0);
            foreach (var child in Children)
            {
                child.Measure(availableSize);
                //use the shortest column
                var col = colHeight.IndexOf(colHeight.Min());
                colHeight[col] += child.DesiredSize.Height;
            }
            return new Size(availableSize.Width, colHeight.Max());
        }

        public double MaxColumnWidth
        {
            get { return (double)GetValue(MaxColumnWidthProperty); }
            set { SetValue(MaxColumnWidthProperty, value); }
        }

        
        public static readonly DependencyProperty MaxColumnWidthProperty =
            DependencyProperty.Register(nameof(MaxColumnWidth), typeof(double), typeof(StaggeredGridPanel), new PropertyMetadata(300d, OnMaxColumnWidthPropertyChanged));

        private static void OnMaxColumnWidthPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            ((StaggeredGridPanel)d).InvalidateMeasure();
        }
    }