The Android Tablets FAQ - For those new to Android

This is a community FAQ here to organize information for Android tablets.

If you want to ask questions, it would be better to start a new thread or to find the correct thread.

Thanks

-xau

Last updated Sept 15 2014.

On Android Features
1) What are the requirements for Adobe Flash on Android?
The official requirements for Adobe Flash on Android include Android 2.2 AND a CPU better or equal to the Cortex A8 CPU. Cortex A9 CPUs including Tegra 2 processors also work. The Cortex A5 and A7 processors also are expected to be supported, but their performance is usually too poor to run most Flash sites well.

While Adobe Flash Player is no longer available on the Google Play Store, it can be downloaded directly from Adobe:
Archived Flash Player versions

Adobe's official statement on this is here:
rich Internet applications | Adobe Flash Player system requirements



There is evidence that Adobe Flash may work on legacy platforms, but this is limited to special versions of Adobe Flash deviating from the official versions released by Adobe. There appears to be several different implementations of this. The versions that run best seem to be on systems with at least Android 2.2. Performance of unofficial versions of Adobe Flash on unsupported platforms is lower than official versions on supported platforms.

2) Can I view animated GIF in Android
The feature of animated GIF files for the web browser was added between Android 2.1 and Android 2.2. All devices Android 2.1 can be configured to run animated GIF files after modifications to system files. However, as GIF files in the browser are demanding on the CPU and memory, it is usually a disabled feature even on Android devices shipping with Android 2.2. There are still issues with viewing GIF files as individual files.

3) Can I view my calendar and email offline with my Android device?
Yes. The easiest way to do so is via the included Google applications on your device. You will need to sync your data to the device periodically by connecting to the internet, where your device your retrieve your data from the Google cloud. Supported Google services include but are not limited to Gmail and Google Calendar.

There are also third-party applications to perform such tasks.

4) Can I watch videos on my Android device?
Video support for Android devices vary, depending on the chipset and associated video decoder employed on the device. Flash video depends on support for Adobe flash. However, some web services such as Youtube have videos formatted for mobile devices and does not require Adobe flash to view.

With more recent products with Cortex A8 or better, the device may contain a technology called NEON, which allows you to run apps that can do the decoding for you efficiently. Examples of these applications include MXPlayer, and DicePlayer.

5) Can I rotate the screen on my Android device?
Many Android devices have built in G-sensors (accelerometers) that detect the orientation of the device and rotates the screen. However, this may not always be implemented correctly, or disabled altogether. Make sure you have not enabled the 'lock rotation' setting.

About Android Tablets
1) Where's a good list of Android tablets I can start off with?
Wikipedia: List of Android devices - Wikipedia, the free encyclopedia

When in doubt, the Google Nexus tablets are a good choice. Google guarantees software updates for these tablets, and this is still very important for tablets as the tablet oriented features of Android are just beginning to mature. Many tablet manufacturers do not deliver in updating Android.

2) How is the market like for Android tablets today?
Many major electronics brands now manufacture Android tablets, including Acer, ASUS, Lenovo, Samsung, Sony, Toshiba. There are also many secondary manufacturers which may cost less but may result in a compromise in customer support, device quality, or future firmware updates.

Unless you are fairly confident of the quality of the gadget you are purchasing, with any expensive electronic device, it is good to have manufacturer warranty. If you are not a careful person, considering SquareTrade for some extra warranty protection.

Beware of the many low cost tablets from China, typically below $200 and originating from Shenzhen shanzhai factories. Shanzhai factories have traditionally been involved with cloning cellphones, and other consumer electronics. However, tablet devices or MID (mobile internet devices) are becoming more and more popular, as it is far less risky to manufacturer and has far fewer legal implications such as IMEI faking. These are lower end devices with poor support and quality control, and are generally not recommended. You will find many such listings on eBay. The safest bet is to buy from a brick-and-mortar retail store, or from the Google Play Store (if available in your country). Make sure you have warranty from the original manufacturer to avoid any issues. There are reputable non-international brands in China such as Oppo and Xiaomi which will have better quality. .

3) Is there firmware support for my tablet?
It depends on your manufacturer's willingness to provide the firmware for its end-users. Typically manufacturers will give more suport to flagship devices that are more popular.

When in doubt, stick with a Nexus.

Qualcomm based devices generally have better support than other SoCs because of their popularity. Intel and Nvidia devices can be hit or miss. MediaTek and Marvell devices are usually a disaster.

4) Can I upgrade the RAM in my tablet?
Typical tablets are embedded platforms, and do not have replaceable RAM modules. They are closer to the smartphone than a netbook. So no, you can't just upgrade the RAM in most cases.

5) Can I upgrade the ROM (storage space) in my tablet?
Usually not. The flash memory ROM chip is typically soldered on the mainboard and is not end-user replaceable.

Some tablets have external storage in the form of a microSD card. Recent versions of Android do not allow the installation of applications or application data on to external storage devices. When you are allowed to move applications to the external microSD, this may involve some sort of annoying manual procedure.

6) Can I charge my Android tablet with the USB port on my computer?
Depends. If it changes with the USB port of your computer, it does so quite slowly. USB ports are usually not enough for charging Android tablets due to the electrical design of the tablet itself and the low amount of current a USB port typically supplies. For best results, stick with the charger that comes with the tablet.

7) What is a good size for the Android tablet today?
If you buy a tablet today with Android 4.0 or greater, you can pick the size you want and not be worried about whether or not apps will look good on the device.

Typically you want a 7-8" Android tablet to take advantage of phone apps that look decent even for this form factor. The popularity of the Nexus 7 means that there are more apps optimized for this size. 1280x800 is the lowest resolution you should go with before losing a significant amount of screen fidelity.

Getting a device with a non-standard screen resolution results in application incompatibility and breakage. 10" tablets do not as many well optimized apps optimized, but this is a great size to use for reading documents.

8) Who makes my tablet?
Just as with any other electronics product you buy today, an Android tablet is made up of different components and is a joint effort by multiple companies.

If you bought a generic shanzhai tablet, the manufacturers usually like to hide their manufacturing chain. It is usually a multi-company effort to produce a tablet. Involved parties typically include: the chipset manufacturer, the assembly factory, the original design manufacturer (product design and conceptualization), and the electronics developer (also in charge of firmware, sometimes whose function is replaced by the chipset manufacturer).

If you need help figuring out what you have, start here: http://www.androidtablets.net/forum...d-system-info-display-device-information.html

9) My tablet looks the same as another tablet? Is it safe to assume that this is the tablet I have, and that I can go ahead and use the firmware designated for that device?
Not necessarily.

Do not flash a firmware that was not intended for your device. You might end up with a brick no one can fix.

Going by outer appearances alone for unbranded tablets is not wise, because some manufacturers are known to swap the internals of devices without any changes to the outer appearance. This practice is confusing for consumers, but saves money from a manufacturer's point of view. As such, this practice is not going to stop any time soon. This happens less often with branded devices. But if the brand is just rebranding existing generic devices rather than developing them, they cannot control this behavior.

10) Can I install Microsoft Windows on my tablet?
Microsoft Windows usually has no support for the type of hardware used by most Android tablets. As such, you generally cannot install Windows onto an Android tablet.

There are some rare exceptions to this, specifically if the processor has an x86 architecture. There are some Android tablets that dual boot Windows based on x86 Intel processor. In these cases, be prepared to do a lot of research to get this to work, because even then the bootloader and driver differences do make it scenario unlikely even with fully capable hardware.

11) Can I install Android tablet or computer that already runs Windows?
The Android x86 project is an effort to attempt to allow x86 computers to run Android. Currently, the project is run by volunteers with limited resources. As a result, there are not many x86 computers that actually perform as expected when running Android. The project offers bootable USB images you can try to see the level of compatibility with your device.

12) Can I expect to use my USB mouse/keyboard/storage drive with my tablet?
This depends on the manufacturer. If there is support, you will need to obtain a USB OTG dongle or cable. The port needs to be connected in a specific way inside the tablet for USB peripherals to work. Generally, you can expect mice, keyboards, and storage drives (FAT) to work if your device does support this feature.

 

About Android
1) What is root and why do I want to root?
Read this thread: http://www.androidtablets.net/forum...resource-what-rooting-why-do-i-want-root.html

Some key benefits of root include:

• system customizations, such as with with Xposed Framework http://repo.xposed.info/
• system wide ad-blocking
• removal of stock firmware bloat

2) What's the newest version of Android right now?
Android L. The previous version of Android was 4.4 and was also called KitKat. Android 4.1 to 4.3 were all called Jellybean.

As of this writing, Android 4.3 brings TRIM support to Android, which is crucial for long term device performance. As such, it is not recommended that you go and buy a device with less than Android 4.3.

3) Can I upgrade my Android version to the latest version?
Upgrading Android is not always trivial, and typically is not supported by the device manufacturer for many of the devices you can buy today, especially when it comes to Android tablets.

The alternative is to look for good third-party support, such as via Cyanogenmod: http://wiki.cyanogenmod.org/w/Devices

4) What is a list of officially supported screen resolutions of Android?
Android 4.0 supports a large range of screen resolutions, making the following information obsolete. You generally don't have to worry about screen resolution support if you have Android 4.0 or higher.

But if you are considering an Android 2.x device, the following information may be of interest to you.

As of Android 2.2, Android officially supports 854x480, 800x480, 480x320, and some more smaller screen sizes. Any resolutions not listed can likely result in application incompatibility. Android 2.3 adds support for larger sizes, such as 1280x800, up to 10".

Android 3.0 is a version of Android designed to be used for tablet use. New tools allow programmers to create applications that work better on larger screens. It also allows richer content. The optimized resolution is 1280x800 for this version of Android.

You can find that information via Android.com, here:
Supporting Multiple Screens | Android Developers

(updated for Android 2.2)

5) What is, and why do I want a custom recovery? Also more information on how firmware updates work.
A recovery image refers to a reduced functionality mode the tablet can boot into to perform system recovery, factory resets and data wipes, or system updates in the case of most standard Android devices.

Android updates are typically delivered in an 'update.zip' format, which is a specially signed and packaged zip archive containing scripts and files pertaining to a system upgrade. However, not all manufacturers follow this scheme of updating the firmware. The recovery image can be regarded as a separate operating system (like booting Linux on a PC running Windows) that allows you to perform modifications on the designated operating system (in this case, Android).

Custom recovery images, such as Clockworkmod or TWRP Recovery, are modified recovery images (or modified recovery operating systems) that extend the functionality of manufacturer original recovery images to allow for user modifications. In particular, it allows for users to install their own custom 'update.zip' packages. Users can then deliver their own system modifications easily by sharing their own packages.

Another important function typical with custom recovery images is the inclusion of a script called 'nandroid', which creates full backups of the running system and all associated data in the form of a disk image. The nandroid backup files can be easily restored to rollback the Android operating system to a previous backed-up state. This also allows users to attempt drastic changes to their operating system without risking the loss of user data.

Some manufacturers defer to a low-level firmware flash for firmware upgrades, which involves booting the device into a special bootloader mode to flash the firmware. This takes place automatically in some cases, provided that the correct files are placed either in the internal memory, or on an external SD card. Others use an external update server to serve firmware over-the-air. Some devices have been noted to ship without a bootable recovery image, or one that has been heavily modified that it is more difficult to deploy the functions of typical Android custom recovery images for the platform.

The standard custom recovery is the best way for users to safely modify their firmware, and roll back any changes.

 

For Android and Firmware Developers
1) Where do I get started?
Android.com - Android at Google I/O
https://android.googlesource.com/

2) How do I make a custom firmware for a device?
You need access to a Unix based environment to be able to unpack and repack the firmware contents, as they use file permissions that are not compatible with Windows file systems.

The structure and layout of the firmware packages typically depends on the chipset manufacturer.

Firmware developers are capable of modifying or adding features to existing firmware by writing or applying their own written code. This typically means downloading the Android open-source project in its entirety and compiling portions or all of it.

Firmware cooks typically refer to individuals who swap in components of an existing firmware, mixing and matching components to 'cook' a firmware. Cooks may also spice up the firmware by adding in small tweaks and parameters. Repackaging existing applications and theming would also constitute to cooking. While cooks do not significantly modify the underlying behavior of the existing firmware distribution, they tend to the needs of the community by performing small detail changes firmware developers otherwise may not have time to complete.

3) Is the kernel source code, or any source code available for the device?
It usually depends on how big the chipset manufacturer firm or original design manufacturer is. Even though the Linux kernel falls under the GPL, foreign manufacturers have ignored this. Here's an excellent article to get an idea of how bad it is:
Project Gus » The Sad State of Open Source in Android tablets

A page tracking the state of Android tablets and GPL compliance is here

 

@soupie2774 Not sure how to help. Beyond reflashing the firmware there's not much to do for the typical end-user

@Draugr I am probably not the best person to answer those questions, but my understanding is that the Android market is a part of the Google mobiles applications package that requires the manufacturer to be a part of the open handset alliance to use legally. The problem with tablets without the Android market is not because the market is not ready for tablet apps, since there isn't really any distinguishing of tablet or phone apps, but the tablet manufacturers not willing or not able to acquire the Google mobile applications package and the Android Market that it comes with.

When you connect to the market, it does cause some apps not to show up if you do not have a particular model. But the majority of the apps on the market have no such restrictions, whether it be an Android phone or tablet.

 

Tupin: TCC8902 based tablet is what would be best for movies. But they are just coming out, and I'm not sure if Android market is fully functional on all of them just yet. Keep an eye out for those.

ddruziak: If you have a Rockchip, chances are that you need a firmware update

 

Thanks for setting this up and getting it started.
Q. What is the ideal and available tablet that would be suited best to start programming for?

My thought is to focus on one device that provides the best platform for doing development for. I have Eclipse and the ADT up and running and have delivered code there.
Now, I want to know next steps. Like building a ROM or whole-new release of the running OS on the device. As well as tablet specific development.
Can you add some details for where you would suggest I get this information?

Thanks in advance