Apple

iPad Weight

Sunday, 15 August 2010 15:26 Written by John Spade

Apple made a big deal about the battery life on the iPad but I find I could easily live with 1/3 to 1/2 the battery life in exchange for weight. I thought about replacing the battery with a smaller one, but it looks like it would not make a whole lot of difference as posted by Kyle Wiens on ifixit.com.

-snip- in case link changes

Here's our summary:

Aluminum back 138 grams
Battery 148 grams
LCD 153 grams
Glass (and frame) 193 grams
Speaker: 17 grams
Main board: 21 grams
Everything else: 27 grams

Car Charger Review

Wednesday, 11 August 2010 08:20 Last Updated on Wednesday, 11 August 2010 09:35 Written by John Spade

If you have an iPad or iPhone 3GS+ then this is the car charger for you. The Griffin PowerJolt and PowerJolt Plus allow for full 2.1 amp charging via a 12 volt source. Also, the passthrough socket will allow you to plug another charger or device in through it's passthrough port.

My favorite thing ( besides rapid charging) is that it seems to run cooler than any of the OEM chargers. power jolt plus car charger Charge rate was most noticable on my iPhone 3GS where the charge level increased around 2% per minute during the phase 1 charging. The ability to fully charge my phone in about in hour means I don't have to top off every time I think about it which is detrimental to long term battery life.

iPad charging was good and it was able to charge the iPad while it was awake and busy. Some chargers or cables don't have enough juice or throughput to charge the iPad while in use. This one is 'a-ok'.

global iPhone / iPad code PDF code exploit

Monday, 02 August 2010 12:20 Last Updated on Thursday, 12 August 2010 08:54 Written by John Spade

UPDATE: iOS releases 4.0.2 and 3.2.2 close this hole as of Aug 11 2010. No fix for 2G models still in service ( serveral million? ).

Yikes!

New jailbreak via jailbreakme.com ( not a link because it opens directly to jailbreak site ) exploits what appears to be a global hole in PDF viewer on the iPhone, iPod touch, and iPad. While the jailbreak itself may be safe to run, the exploit could be used to execute malicious code. A quick test showed that when emailing myself a PDF file of this style, it was executed just upon viewing the email ( see link below ). Apple will have to issue a fast patch on this and in the mean time, setting the preview to none may help. This could be a disaster if it is the top email in your inbox, in which case it executed when the email is previewed upon opening. Please let me know if you find a way to disable PDF preview or opening.

To be clear, in order to execute the code, it does not require a phone to be jailbroken. It also appears to work in almost every common version of Apple iOS, not simply the newest one. The only good news is that it does not automatically execute in every version, some have to be clicked. Unfortunately, if a user thinks they are just opening a PDF document, this does not seem to be much of a barrier.

How the jailbreak triggers behind the scenes : <a href="/iPhone1,x_4.0.1.pdf">iPhone1,x_4.0.1.pdf</a>

If I was more creative, I could probably do somethign nefarious to my iDevices. What is scary is that it works via Safari or email. In email it apparently only has to preview the PDF to execute the code. Here is a quick video showing an example. It seems to be in the PDF viewing itself and not something new that was added via iBooks. More info as I discover it.

Update:

Ok so found it documented here from the people who released the jailbreak. They show a way to close the exploit until Apple releases a patch or workaround. Here's the irony, you can only apply the fix if you jailbreak your device ( recent favorable opinion on jailbreaking ). Also, when Apple releases the update, it will likely require you to update the software, so you may be forced to go to a version you are not keen on. Alternatively, you could just not open any emails or click any links. Good luck with that.

Corporate IT administrators may want to think about quarantine on all PDF attachments and blocking direct PDF links to iPhones via centralized web proxy. This does not, however, prevent a user's phone from being compromised via 3G or another network as they roam about.

iPad USB charging hack

Wednesday, 28 July 2010 08:42 Last Updated on Saturday, 21 August 2010 15:47 Written by John Spade

ADVANCED: This article describes how to update your USB drivers on certain systems to allow higher current charging if only one device is plugged into that group of ports. I will be updating this as i go along but this works on my PC's with ASUS motherboards ( ASUS and HP ) and so far it is working on my Lenovo Thinkpad T400. This may provide the perfect marriage with the Y USB power splitter cables. If anyone has pinout for one of these cables, please contact me. Amazon and other vendors sell such cables but I'm curious as to the construction. Just marrying the +/- 5V does not appear to be correct. DISCLAIMER: warning, there is a chance that this could burn out your USB port or device, though most good boards should protect themselves. Not responsible for damages, no warranty expressed or implied, risk of fire, etc.

This seems to work on boards with Intel ICH9 and 10 chipsets. ASUS has published a driver update that seems to work on some boards with Intel USB root hubs. I have not tested it yet with the iPad battery below 80% where it would draw more power but it worked in the top end. I was able to have the device awake playing Pandora and it shows charging AND the battery level increased. When I attempted to plug it into a port where there was another USB device on the same 'hub' it disabled the internal hub and both devices lost power. Was able to reset it and separated out all my devices.

iPad Charge Cable

Monday, 26 July 2010 08:26 Last Updated on Monday, 02 August 2010 13:34 Written by John Spade

Some people have noticed that the iPad will not charge on some after market cables, especially if they are longer than the standard charge and sync cable. In fact I have seen this on standard length cables where the iPad battery drops even though I have it plugged into the ipadnotcharging charger it came with and it says charging.

The reason for this is pretty simple. USB charges around 5 volts and if you are expecting the over 1 amp ( 5 watts ) on the standard cable, it better not be very long. This is because the size / gauge / AWG / diameter of the wires is too small. By specifications, USB 2.0 cables can have wires with AWG as high ( small ) as 28.

First a table of solid core wire AWG for power transmission ( most USB cables have stranded wire for more flexible cables ). The following is a table that shows common iPhone or iPad charging methods, for nerds the values are approximate and designed to carry the 'concept' and length is length of cable but AWG for true 'round trip'. Smaller AWG means a thicker wire. Data from Powerstream calculator.

Charger	Current/Power	3ft AWG	6ft AWG	10ft AWG	Approx Voltage Drop
PC USB	0.5A/2.5Watts	28	26	24	0.4
iPhone 3GS	1.0A/5.0Watts	26	24	22	0.5
iPad	2.1A/ 10Watts	22	20	18	0.5