It is inconsistent with Android where the lines are not present and the background is transparent.

Workaround: 

<telerikChart:RadCartesianChart.Grid>
                <telerikChart:CartesianChartGrid x:Name="grid" StripLinesVisibility="None" />
</telerikChart:RadCartesianChart.Grid>

or:

chart.Grid = new CartesianChartGrid() { StripLinesVisibility = GridLineVisibility.None };

Available in the 2018 R2 SP release.

NSRangeException is thrown when second series has more items than the first one on iOS.

Available in the R3 2018 SP release.

LineSeries.Stroke and StrokeThickness are not applied when Palette is set

DateTimeContinuousAxis labels are off by one hour when device is in DST zone (Android).
Available in the R3 2017 release.

DateTimeContinuousAxis does not display afternoon times correctly. They appear as 'AM'

The issue is present in a quite specific setup where а CartesianChartGrid is placed within the first column of the following Grid element:
 <Grid BackgroundColor="Red">

        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="15*" />
            <ColumnDefinition Width="10*" />
        </Grid.ColumnDefinitions>

If you change the proportions to "150*" and "101*" the issue is not present anymore.

With the current release the chart does not update its series (and axis) when the BindingContext is set on a button click.

Available in minor release 2017.3.927. It will also be available in the R3 2017 SP release.

When you declare a specific CalendarAppointmentsStyle and assign it to the AppointmentsStyle property of the RadCalendar - it is not respected. However, if you try to set it in the NativeControlLoaded event, the changes are correctly applied. 

Available in minor release 2018.1.405. It will also be available in the R2 2018 release.

Bars are too thin in iOS when items are per day.

Available in the R3 2018 SP release.

A possible workaround is to manually set the MajorStepUnit and the MajorStep properties according to your setup.

Edit: Avalable in R3 2017 SP release.

This is visible only with longer labels, check the attached image.

After setting the MajorLinesVisibility property to GridLineVisibility.Xy only the Y lines are showing up.

After setting properties like FillColor, LineColor, LineThickess, etc. they are overridden by the Chart default palette.

Available in minor release 2017.2.0602. It will also be available in the R2 2017 SP release.

Categorical series that have multiple data points in the same category do not stack correctly.

Edit: Avalable in R3 2017 SP release.

The chart BindingContext does not propagate correctly to some of its children, e.g. axes and grid.

Available in the R3 2018 SP release.

If customers set bindings to these properties and try to set range from negative to positive values (e.g. from -0.5 to 0.5) the bindings are not applied as expected.