Recently, Elephone has launched S3 Lite smartphone with features like a 1920 x 1080 pixels resolutions on a 5.2 - inch Full cell laminated display, which gives a pixel density of 423 PPI.
If you have access to a laminating machine, you can laminate your banner so that it is durable and you can use it year after year for your bulletin board display of these Cell Phone Book Report Projects.