"We don't have plenty of bandwidth with mobile applications." Because mobile devices have screens with 300ppi it's not a bad idea to use GIF or PNG files with

"We don't have plenty of bandwidth with mobile applications." Because mobile devices have screens with 300ppi it's not a bad idea to use GIF or PNG files with less than 64 colors (adaptive). When you use dither (patern) the results are quite good given the filesize.