I looked at the possibilities of the RadCalendar and it looks great.
But there is one point that is important to me, but I have not found an opportunity to apply it.

The CalendarViewMode.Day displays the time from 01:00 till 00:00
Is it possible in Radcalendar to limit time in CalendarViewMode.Day? (for example from 08:00 till 18:00 o'clock)

Hello, Dmitry,

I am glad to see that the Calendar seems suitable for your requirements.

As for the specific functionality you are looking for, you can achieve the behavior by directly modifying the native controls in Android and iOS. Basically, you need to create custom renderers and directly work with the API of the native controls in the platforms. I have attached a sample for your reference. Please have a look at the custom renderer classes. 

We also have a feature request to expose the functionality in Xamarin.Forms so that no such additional effort is required from your side. Furthermore, we will consider providing mechanism to programmatically scroll to a certain hour/event. You can track the progress of the feature request on the following link from our Ideas & Feedback portal - Calendar: Add possibility to change default time period range. Please subscribe to the item so that you receive automatic notifications when there are any updates.

Have a great week.

Regards,
Stefan Nenchev
Progress Telerik