The Apple Peel 520 case is designed for the iPod touch and has been designed to turn the iPod touch in to an iPhone. The case of course is not an official Apple [AAPL] product and from what we have heard, it isn't 100% perfect, but it does allow you to put a SIM card inside the case and make calls from the iPod touch.
Price wise, it will set you back about $57 when it launches although the product reviewed over at PCOnline is a prototype as the final models are not ready for launch just yet.
So, let's start off with the highlights. This Apple Peel 520 slap on a regular SIM card and make calls with your iPod touch. It does not support 3G, but includes a removable 800mAh battery which gives you up to 3 hours of talk time and 120 hours of standby juice. The funny thing is that when the battery is installed successfully, the adapter itself will vibrate, so we're guessing it supports vibration.
To get the case working, it requires you to jailbreak your iPod touch so that a couple of necessary apps can be installed. These are the Phone app and the Messaging app so you can get text messages and make calls.
Users need the 'Yosion and 'YsSMS apps on the homescreen to start using the adapter.
The final versions we hear will have Bluetooth compatibility allowing you to use a headset with the case.
Problems noticed so far...
# iPod touch shows 'Calling even though the call is picked up.
# Incoming phone numbers and contacts may not appear.
# If there's missed calls, you may receive 'blank messages for reminder.
# Ringtones could not be set up for incoming messages and calls, the device will vibrate and rings by default. The default ringing sound can be disabled.
# You can adjust the call volume, but there's no difference after adjusting.
# When there's incoming calls, the display of the iPod touch will not light up, and the accepted call could only be hung up by the other party.
# The SMS text is smaller than the text on iPhone.
# Deleting and forwarding a single message is not available.
# The draft will still appear in creating new message even though the message is sent.
# Adding multiple recipients at the same time is not allowed.
More pictures and a video of the adapter can be found over on MIC Gadget.