IPod that put "1,000 songs in your pocket." Apple did not develop the iPod software entirely in-house, instead using PortalPlayer's reference platform based on two ARM cores. The platform had rudimentary software running on a commercial microkernel embedded operating system. PortalPlayer had previously been working on an IBM-branded MP3 player with Bluetooth headphones. Apple contracted another company, Pixo, to help design and implement the user interface under the direct supervision of Steve Jobs. As development progressed, Apple continued to refine the software's look and feel. Starting with the iPod Mini, the Chicago font was replaced with Espy Sans. Later iPods switched
IPod Touch to the iPod Touch as "training wheels for the iPhone". All iPods lack Touch ID, 3D Touch, NFC, GPS, an earpiece speaker and a noise-cancelling microphone. Depending on the generation, the iPod Touch may have a smaller or inferior display and camera(s). Newer models (5th and 6th generation) lack the ambient light sensor that makes automatic brightness available. Older models lack a built in speaker, a microphone, a camera, and a flash. No iPod Touch has a modem through which it can place phone calls or send SMS and MMS. However, 5th and 6th generation models can either piggy-back on