05dec11

= 05 December 2011 LUG meeting notes =

We had our last EUMETSAT GNU/Linux User group meeting of the year on 5-December-2011. The topic was 'Android Tablets' where we presented the user interface of an Asus Transformer. (Presentation was conducted by L.Matheson)

Asus Transformer (TF-101) Specification
The tablet present was an Asus EEE Pad Transformer - specific model number was TF-101B1 (which does not have 3G). There is an Asus Transformer with 3G which is the TF-101G.

Interfaces in TF-101
Interfaces in the TF-101B1 Tablet portion include
 * power-on/off
 * front and back camera
 * speakers each side
 * +/- volume control
 * integrated mic
 * single combined audio/mic in/out jack
 * micro SD card slot
 * 802.11n Wi-Fi, Bluetooth
 * dockingstation adaptor (where one can plug in proprietary Asus adapters for USB, full sized SD card, power/recharge cable ... )

The TF-101B1 came with Android 3.1 and was updated within a few days after initial switch on by an Asus pushed download to Android 3.2.1. The Linux Kernel version with this Android version is 2.6.36.3.

CPU: 1GHz Nvidia Tegra 2 dual-core Cortex A9 processor. The presenters Transformer has 1GB RAM and a 32-GB integrated SD card (for storage).

The screen is a 10.1-inch (1,280 x 800-pixel) touchscreen (colour).

Android Desktop GUI
The desktop GUI was demonstrated, and a number of apps illustrated. The view of the presenter (myself) is there are many thousands of Android applications, so when the 'press' globally states Android is lacking in applications, that is misleading as there are a massive number of applications for the Android OS. What is noted thou, is many of the Android apps are optimized for mobile phones, and hence while functional on a Tablet, they do not have the same glossy/slick/properly-sized look that one will often get with iPad2 functionally equivalent Tablet applications. The number of Android applications specifically 'optimized' for a Tablet are in the view of the presenter, lagging the number of Apple applications specifically optimized for a Tablet.

The Tablet was noted useful in viewing office documents (Word, Excel, Power Point, PDF files). The Android application's edit capabilities are limited by keyboard functionality, which is helped significantly with the Transformer dockingstation/keyboard, but its still not as good as Windows7 when it comes to creating/editing documents.

The capability to view PDF documents was noted, but no PDF edit applications (via hand writing on the Tablet) are known by the presenter.

The capability to view Excel spreadsheets, with the touch screen, was noted to be very useful, and large spreadsheets that can frustrate users with 17" laptops, was noted very easily viewed and scrolled (ie superior to view) with a touch screen tablet. This lead the presenter to speculate that within some TBD time in the future (10 years ?? ) that touch screen displays could replace non-touch screen displays for all notebooks  and many desktop computers.  As it is now, when going back to a desktop PC after using  the Tablet, the presenter definitely misses the ability to scroll with a touch screen (as mouse is not as capable as a multi-touch screen for this functionality).

Asus Transformer Accessories
The presenter noted accessories he had procured were:


 * HDMI to VGA adapter (permits displaying the Android desktop on an external monitor/projector). This has limitations (part of screen not projected, and no audio in this mode)


 * USB Adapter - allows to use USB devices direct to Tablet (without dockingstation/keyboard). Presenter has tested USB sticks, 1 TB USB external drive, Canon Ixus-800 IS digital camera, all of which functioned ok. It is noted this adapter is very loose and can fall off easily.

Asus Transformer Docking Station / Keyboard

We also had an Asus Transformer Dockingstation keyboard present, where the Dockinstation keyboard provides:
 * provides an additional battery
 * provides 2 USB ports
 * provides a MMC/SD/SDHC card reader
 * provides a netbook sized keyboard with touchpad

The dockingstation keyboard 'for me' is more useful wrt its additional battery, where the Tablet portion alone has only an 8-9 hour life, while with the dockingstation keyboard plugged in, the battery life is extended to 16-hours.

The keyboard is 'netbook size' which I find a bit small for my larger fingers and tendency to touch type (which I can not reliably do on a netbook keyboard).

An alternative to using the dockingstation keyboard is a bluetooth keyboard, and there are reviews on the Internet of people who have successfully used a bluetooth keyboard with the Asus Transformer.

I've read reviews where USB keyboard also works with the Asus Transformer, but one would need to use the 'USB adapter' to connect a USB keyboard, and my experience with the 'USB adapter' is its 'fit' is very loose and it has a tendency to fall off, and thus not suitable to interface a USB keyboard to the Tablet portion. I've read reviews where a USB keyboard has been interfaced successfully to the dockingstation keyboard (providing a full sized USB keyboard) but that's more for home than for travelling.

Android Tablet Philosophy Comment

 * One comment of the presenter on Android operating system, is it is not structured like a typical GNU/Linux distribution. One needs to rely on the hardware supplier to update the Android version, because typically proprietary drivers (for hardware) are not readily available to the users to apply when updating themselves the operating system from Google. Hence it may be prudent to procure an Android Tablet from a supplier that has a long history of software support for their hardware as else one may end up with a Tablet with no more direct operating system support.


 * Tablet security - The Tablet comes with no anti-virus software, nor firewall. Hence it is not clear it has adequate security for use with one's sensitive data, and the presenter is hence not using the Tablet for any private/work confidential nor financial / banking / credit card dealings.


 * App Shop/Store - The presenter only uses the 'default' Google/Android APP Shop (which is in essence an Android GNU/Linux software repository). There are other App Shops for Android, but those Ap Shops do not provide the same security checking of their applications, and hence one takes more of a security risk when using the non-Google/Android App shops.

Merits of 3G Connectivity in Tablet
The presenter noted having 3G in a Tablet makes it much more useful, as the Tablet can then be used anywhere with close to full functionality with the associated 3G internet access.

The downside is 3G account can be expensive.

The presenter uses the TMobile Xtra Card (a limited 3G account), which is a 'pay as you go' 3G with very limited speed and very limited bandwidth. Download speed is 384 kbit/sec (UMTS speeds) and upload 32 kbit/s until 200MB of bandwidth used (in 24 hour period) after which download speed drops to 64 kbit/sec and upload to 16 kbit/sec. The TMobile cost is NOTHING if 3G modem not used. When 3G modem is used cost is 99 cents for 24-hour period. So if one uses 3G modem for 3 days in a month, then the cost is 2.97 euros.

This for access anywhere and also only in Germany.

Note 3G in general is capable of SIGNIFICANLY faster speeds, but such higher speeds cost more money. I also note this entire 3G market is in flux, and what is true today could change tomorrow as service options are modified.

For a USB modem, the presenter uses an unlocked Huawei K3520 3G modem, purchased used over Ebay.de (for 22 Euros). Originally associated with a Vodophone contract, but now unlocked and it functions with TMobile. The K3520 3G is functionally compatible with the more well known Huawei E169.

Since the TF-101B1 Asus Transformer has no 3G, the presenter uses the Edimax 3G-6218N mobile wireless 3G router (which a fraction smaller than a blackberry Torch phone, and is significantly lighter than a blackberry Torch) purchased for 60 euros. The Edimax has a regular USB port (for the 3G modem stick to plug in) and a mini-USB port for power from a PC or from an adapter. In addition the Edmimax has 4 hours battery life. The Edmimax has 1 Ethernet outlet for an RJ-45 ethernet connection to either receive Intenet (from another router) or to send Internet (when receiving Internet via the 3G modem).

The advantage of using a separate mobile router is one can save costs with only one 3G account. This Edimax router was successfully tested at home with simultaneous connections to: (1) iPod Touch 3rd-Generation, (2) Blackberry Torch smart phone, (3) Lenovo X220 laptop (w/windows-7), (4) Dell Studio 1537 laptop (w/openSUSE-12.1), (5) Desktop PC with atheros compatible wireless card (w/openSUSE-11.4), (6) Asus Transformer. [all at the same time]

Android Tablet Application Comments
Some application specific applications shown:


 * to play HD (high definition) video, such as 720p, it was noted often necessary to re-encode the video to a lower bit rate (easily done from a GNU/Linux desktop with ffmpeg or mencoder). The new coming Asus Transformer prime (which will have a quad-core Tegra processor) likely will not need such re-encoding.


 * an application that connected to a couple of computers at his home (using sftp) illustrating it possible to transfer files (home firewall was setup to redirect to different computers based on port number)


 * ssh into home computer


 * the use of vnc instead of teamviewer by the presenter was noted, because difficulty was encountered with vnc keyboard mapping with the free vnc applications (where TM propagator's mappings were more intuitive).


 * after the meeting it was noted it may be more suitable to use vnc (piped thru ssh) to access one's home desktop PC (so as to launch an application such as TM Propagator) as opposed to using Team Viewer. The full capability of the Android vnc applications to support this piping via ssh needs to be investigated


 * TM-Propagator/Team viewer - this was not demonstrated (as EUMETSAT guest wireless blocks Team Viewer) but noted that with a 3G connection to internet, the presenter was able to take over a WinXP desktop session running TM Propagator (running in Virtual Box on a home GNU/Linux PC) and thus view MSG spacecraft telemetry. This is very useful for when giving support/being-on-call for an MSG spacecraft.


 * Android OS is very limited in terms of providing typical GNU/Linux access. One needs to 'root' their Tablet to obtain such access, and 'rooting' a Tablet may impact the capability to receive updates from the manufacturer.  For example, while its possible to install an APP to get access to the Tablet's terminal/console, the permissions are so restrictive it is not helpful (without the Tablet being 'rooted' ).

Unanswered Questions

 * the utility of GPS Navigation functionality on the Tablet (although it appears there are dozens of applications that provide this - the presenter has no experience here).


 * how to pay for a commercial application (the presenter had only used 'free' applications to date).


 * how to develop Android applications. Is root access necessary ?

I typically bring the Tranformer to work every day, so if anyone wishes to drop by my office to look at it, they are more than welcome.

Lee