I have uploaded an Apple 1 Game in aiff (lossless) format that can be used to load through the Cassette interface from an iPod or iPhone.
Move the file to the iPod through iTunes then connect the iPod to the cassette "From Tape" connector using a 3.5mm stereo miniplug cable. It is best to use a stereo cable because a mono cable will short the Right output of the iPod to Gnd. When loading set the iPod volume to maximum or a little lower. It is useful to have an audio splitter so you can hear the ipod output. The recording is mono and appears on both channels. The game is Hamurabi adapted from 101 Basic Computer Games.
The record loads at 004A.00FFR 0400.0FFFR and runs at E2B3 after Basic is loaded. You can determine whether the load was successful by looking at the last two bytes of the loaded file. Due to the variable length nature of the encoding format it is very unlikely that the last two bytes would be correct if there was a read error anywhere on the record. On this tape the last two bytes, 00FE.00FF should read as 00 ED and 0FFE.0FFF should read as 51 01. If the load at full volume fails turn down the volume about 10% and try again. If you can look at the iPod output with an oscilloscope you can check the volume level. I was able to load successfully over a p-p voltage range of 0.4V to 2V. Note that the LED indicator on the cassette interface will not light up even at 2 volts so if the light is on the volume is too high.
I have several Apple 1 Game files of this quality. They are pretty large files so I am planning to set up a Web site to put these on. I am also writing a description of how to write to the iPod and how i was able to recover the files from my old cassette tapes that were not all in very good shape.
You can look at the file with a free program "Audacity" for Windows and MAC. I used that program to process my files.