SF_10.2, SF_11.0, SF_11.1, SF_11.2, SF_12.0, SF_12.1, SF_12.2, SF_13.0, SF_13.1, SF_13.2, SF_13.3, SF_14.0, SF_14.1, SF_14.2, SF_14.3 - https://docs.sitefinity.com/for-developers-create-new-fields-for-forms#create-the-custom-model-and-controller

YesNoFieldController.cs

using SitefinityWebApp.Mvc.Models;
using System.ComponentModel;
using Telerik.Sitefinity.Data.Metadata;
using Telerik.Sitefinity.Frontend.Forms;
using Telerik.Sitefinity.Frontend.Forms.Mvc.Controllers.Base;
using Telerik.Sitefinity.Model;
using Telerik.Sitefinity.Mvc;
using Telerik.Sitefinity.Web.UI.Fields.Enums;

namespace SitefinityWebApp.Mvc.Controllers
{
    [ControllerToolboxItem(Name = "MvcYesNo", Title = "Yes/No", Toolbox = FormsConstants.FormControlsToolboxName, SectionName = "Custom Fields")]
    [DatabaseMapping(UserFriendlyDataType.YesNo)]
    public class YesNoFieldController : FormFieldControllerBase<YesNoFieldModel>
    {
        public YesNoFieldController()
        {
            this.DisplayMode = FieldDisplayMode.Write;
        }

    /// <inheritDocs />
    [TypeConverter(typeof(ExpandableObjectConverter))]
        public override YesNoFieldModel Model
        {
            get
            {
                if (this.model == null)
                    this.model = new YesNoFieldModel();

            return this.model;
            }
        }

    private YesNoFieldModel model;
    }
}