custom_cell.rb

# code inspired from http://jainmarket.blogspot.com/2009/05/creating-custom-table-view-cell.html

class CustomCell < UITableViewCell

  attr_accessor :primaryLabel
  attr_accessor :secondaryLabel

  def createLabels

    @primaryLabel = UILabel.alloc.init
    @primaryLabel.textAlignment = UITextAlignmentLeft
    @primaryLabel.font = UIFont.systemFontOfSize(14)

    @secondaryLabel = UILabel.alloc.init
    @secondaryLabel.textAlignment = UITextAlignmentLeft
    @secondaryLabel.font = UIFont.systemFontOfSize(8)

    self.contentView.addSubview(@primaryLabel)
    self.contentView.addSubview(@secondaryLabel)

    self
  end

  def layoutSubviews
    super

    contentRect = self.contentView.bounds
    boundsX = contentRect.origin.x

    @primaryLabel.frame = CGRectMake(boundsX+70, 5, 200, 25)
    @secondaryLabel.frame = CGRectMake(boundsX+70, 30, 100, 15)

  end

end

tweet_list_controller.rb

class TweetListController < UITableViewController

#...

  CELLID = "CellIdentifier"
  def tableView(tableView, cellForRowAtIndexPath:indexPath)
    cell = tableView.dequeueReusableCellWithIdentifier(CELLID) || begin
      cell = CustomCell.alloc.initWithStyle(UITableViewCellStyleDefault, reuseIdentifier:CELLID)

      cell.createLabels
      cell
    end

    tweet = @tweets[indexPath.row]
    cell.primaryLabel.text = tweet.username
    cell.secondaryLabel.text = tweet.text
    cell
  end

#...

end