My (probably wrong) way of doing dynamic height UITableViewCells.

TVC.m

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
    CGFloat TEXT_VIEW_MARGIN_X = 14; // gap between edge of cell and edge of text view
    CGFloat TEXT_VIEW_INSET_X = 5; // gap between edge of text view and text inside
    CGFloat TEXT_VIEW_INSET_Y = 9; // gap between top/bottom of text view and text inside

    NSString *text = [self lorem];
    CGSize constraint = CGSizeMake(tableView.bounds.size.width - (TEXT_VIEW_MARGIN_X + TEXT_VIEW_INSET_X) * 2, CGFLOAT_MAX);
    CGSize size = [text boundingRectWithSize:constraint options:NSStringDrawingUsesLineFragmentOrigin attributes:@{NSFontAttributeName: [UIFont systemFontOfSize:17]} context:nil].size;

    return size.height + TEXT_VIEW_INSET_Y * 2;
}

Next step is to make it work with Dynamic Text.