ViewController.h

#import <UIKit/UIKit.h>

@interface ViewController : UITableViewController <UITableViewDelegate, UITableViewDataSource>
    @property (nonatomic, strong) NSMutableArray *data;
    @property (nonatomic, strong) NSMutableArray *sectionTitles;
@end

ViewController.m

#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad
{
    [super viewDidLoad];

    
    NSString *jsonString = @"{\"filter_group\":[{\"filter_group_id\":\"1\",\"name\":\"Location\",\"filter\":[{\"filter_id\":\"2\",\"name\":\"Central\"},{\"filter_id\":\"8\",\"name\":\"East\"},{\"filter_id\":\"1\",\"name\":\"North\"},{\"filter_id\":\"10\",\"name\":\"Northeast\"},{\"filter_id\":\"9\",\"name\":\"West\"}]},{\"filter_group_id\":\"3\",\"name\":\"Price\",\"filter\":[{\"filter_id\":\"7\",\"name\":\"Free\"},{\"filter_id\":\"5\",\"name\":\"$0 - $50\"},{\"filter_id\":\"6\",\"name\":\"$50 - $100\"},{\"filter_id\":\"11\",\"name\":\"$100 - $150\"},{\"filter_id\":\"12\",\"name\":\"$150 - $200\"},{\"filter_id\":\"13\",\"name\":\"Above $200\"}]}]}" ;
    NSDictionary *result = [NSJSONSerialization JSONObjectWithData:[jsonString dataUsingEncoding:NSUTF8StringEncoding] options:0 error:nil];
    
    NSArray *filter_groups = [result objectForKey:@"filter_group"];
    self.data = [[NSMutableArray alloc] initWithCapacity:[filter_groups count]];
    self.sectionTitles = [[NSMutableArray alloc] initWithCapacity:[filter_groups count]];
    
    for (NSDictionary *filter_group in filter_groups) {
        NSArray *filters = [filter_group objectForKey:@"filter"];
        [self.data addObject:filters];
        [self.sectionTitles addObject:[filter_group objectForKey:@"name"]];
    }
    NSLog(@"%@", self.data);
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
}

- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section{
    return self.sectionTitles[section];
}
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView{
    return [self.data count];
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section{
    NSArray *sectionArray = self.data[section];
    return [sectionArray count];
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"testCell"];
    if (cell == nil) {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:@"testCell"];
    }
    NSArray *sectionArray = self.data[indexPath.section];
    NSDictionary *filter = sectionArray[indexPath.row];
    cell.textLabel.text = [filter objectForKey:@"name"];
    return cell;
}

@end