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[ChairmanPoo]

I'm  checking resources online for this matter, but any suggestions that YOU find particularily useful are welcome.

[LeoLeonardoIII]

What kind of tablet? It's important to get it rooted at the appropriate season. For example, most tablets are indoor and like shade, and can be planted around this time, and you'd expect them to root around mid-March. But if your tablet likes direct sun and you don't want to deal with the risk of transitioning from an indoor IT setting to an outdoor area in June, you should probably hold off.

[Tellemurius]

App Ops, control your app permissions so they dont peer into unneeded stuff.

[wierd]

Also, tablet console linux, with proper permissions. (Means running proper system services, and servers on the tablet, mounting remote filesystems properly, and others. Dalvik puts mittens on the user, because most users shouldn't be touching things. Root takes the mittens off.)

[ChairmanPoo]

One thing I'd like to do in particular is move installed apps from the tablet to an external USB I keep and connect with an adapter for that kind of thing. Does anyone know of one?

[wierd]

"Possible".
 Also "very touchy" and "very risky".

Android tablets use a linux kernel underneath. "Android" is basically a linux application suite. It is composed of the Dalvik virtual machine, and supporting binaries.

Dalvik doesn't know one block device from another; it relies on the linux filesystem structure.  If you mount the USB at the /SDCARD mountpoint (and, obviously, mount the sdcard somewhere else!), then android will believe that your USB device is the SDcard. Any application you can push to an SDcard, android will let you move to the USB drive.

To make it do this automatically on every poweron for the device, you have to futz with the device's init scripts. Mangling those can break the tablet what good.

Do a full tablet flashrom backup first, and make sure you have something like clockwork recovery mod installed so you can recover in case you accidentally brick.


Doing this will require some more detailed knowledge about the tablet's rom, and how it was cooked. (Initd flavor, etc.)  You also need to know what filesystem drivers are baked into the rom, so you can pick an appropriate one. I *strongly* recommend a journalling linux filesystem flavor. EXT2 is most likely to be supported by anything in the android ecosystem, but DOES NOT have a journal. Since the device is going to be dangling outside the tablet, the risk of physical disconnection "unexpectedly" is high. That is why you need the journal, unless you LIKE filesystem corruption, of course.   EXT3, EXT4, ReiserFS, BTRFS, and pals are all possible choices. See which FS drivers are baked into your kernel with a root console application with lsmod.  That will list which kernel modules are loaded. I suggest at LEAST EXT3FS.

If your device has an sdcard slot (not all android tablets do!), then you would probably like to retain access to it. Dalvik/android doesn't have good support for multiple sdcard slots. It's kinda dumb that way.  Instead, just create a mountpoint for it that is a folder underneath the /sdcard mount that you are mounting the USB device on. Something like say, /sdcard/realsdcard or some such.  Just make an empty folder called realsdcard on the mounted USB device, and point the mount command in the init script there when it mounts the sdcard block device.  You will then be able to use the physical sdcard as well as the USB device.

(The contents of the sdcard will appear in the /sdcard/realsdcard folder. Writes to that folder when the block device is mounted will physically occur on the sdcard.)

[freeformschooler]

You can make the processor run at "all the GHz" until it blows up. Why else would you root your tablet?

What kind of tablet? It's important to get it rooted at the appropriate season. For example, most tablets are indoor and like shade, and can be planted around this time, and you'd expect them to root around mid-March. But if your tablet likes direct sun and you don't want to deal with the risk of transitioning from an indoor IT setting to an outdoor area in June, you should probably hold off.

Thank you for this post.

[wierd]

Yeah, you could probably change the power management policy to keep it from throttling the cpu, but that is NOT desirable.

Really. It simply isn't.

[freeformschooler]

weird: would it would be less preferable for higher power processors, though? I am curious because, occasionally, I do this to my cheap ZTE when playing games or what-have-you. It doesn't get hot, but my brother's (more powerful) phone does, so he doesn't change the policy.

Blowing up electronics is never preferable. Take regular breaks from Borderlands.

[wierd]

Make sure it's on external power.

LiON batteries will wear out fast under constant heavy discharge. The power management policy is in place not just for heat, but to keep the battery from being killed as well.

[Tellemurius]

One thing I'd like to do in particular is move installed apps from the tablet to an external USB I keep and connect with an adapter for that kind of thing. Does anyone know of one?

Unfortunately not possible, Kernel will view it as an external usb storage and will treat it like one. Even if you were to somehow trick it to be a type of internal storage the app has to support multiple partition and most don't. What i did with my phone is set the sd card as a media storage for my pictures, music and videos, and my backups for the system. Google Music is set to save its cache into the sd card, after all of that, i saved 6gb of internal storage.

[wierd]

Tellemurius:

There is "kinda sorta" a version of ./etc/fstab in android devices.

You can forcibly change the way block devices are mounted by futzing around in there. The problem is with supported filesystems, and what manner the rom was baked, exactly what you can accomplish there.

I am using a community cooked froyo custom rom on my current phone. (Its old.) It has ext2fs support, so I use ext2fs on my sdcard so I can have linux permissions there. It has 2 partitions so I can keep a clean android linux jail. On my device the block device ID for the second partition on my sdcard is /dev/block/vold/179:2 (partition 1 is /dev/block/vold/179:1) the system only mounts the first partition at /sdcard on startup. The other partition is inaccessible until I initiate the chroot script, which mounts it at /mnt/Linux, then chroots there. I *have* successfully manually mounted it within the /sdcard mountpoint on a subfolder, to access it without entering the jail.

If he can consistently know what the block device ID for his usb device will be, he can make it mount at /sdcard instead of the sdcard's block device. Then android won't know that his usb device is not the sdcard slot.

[Tellemurius]

Tellemurius:

There is "kinda sorta" a version of ./etc/fstab in android devices.

You can forcibly change the way block devices are mounted by futzing around in there. The problem is with supported filesystems, and what manner the rom was baked, exactly what you can accomplish there.

I am using a community cooked froyo custom rom on my current phone. (Its old.) It has ext2fs support, so I use ext2fs on my sdcard so I can have linux permissions there. It has 2 partitions so I can keep a clean android linux jail. On my device the block device ID for the second partition on my sdcard is /dev/block/vold/179:2 (partition 1 is /dev/block/vold/179:1) the system only mounts the first partition at /sdcard on startup. The other partition is inaccessible until I initiate the chroot script, which mounts it at /mnt/Linux, then chroots there. I *have* successfully manually mounted it within the /sdcard mountpoint on a subfolder, to access it without entering the jail.

If he can consistently know what the block device ID for his usb device will be, he can make it mount at /sdcard instead of the sdcard's block device. Then android won't know that his usb device is not the sdcard slot.

You don't understand, in order for his usb storage to work the kernel needs to switch into USB Host mode. This allows the phone to increase the output voltage and amperage so your device will run. The issue is that the usb is assigned as a external path within Android (its essentially in slave mode) and isn't something you can change instantly, you are talking about modifying firmware here along with android itself. With the newer editions of Android it is very easy to setup and mount separate system partitions with in the internal storage and External SD, this is possible cause how Android hosts the External SD within the system.

Summary short: He would need to change his USB driver to always be in HOST mode while also allowing the same functionality of charging and syncing with a desktop. Never have i heard a dev attempted something to the likes of this and its way beyond Android coding, we are talking about Manufacturer Firmware that today we are even lucky to see.


Also, Froyo is terribly outdated my friend Once Gingerbread was merged with Honeycomb, Android skyrocketed with OS Functionality.

[wierd]

(Froyo == old)

Oh, I know....   however, the phone has not died yet, and is still functional. When it finally gives up the ghost, I will upgrade, but not before.  I did not get the phone on a subsidy plan, so I can't just "upgrade it away".

The hardware for the phone isn't that bad: 1ghz hummingbird with 512mb memory, hardware keyboard. Though the gpu is not so hot. (PowerVR, IIRC. Blech.) Considering it is a froyo generation device, its not that bad for hardware. (It really should have gotten ICS, but the carrier decided I didn't need it, and instead needed a new phone. I don't feeling like upgrading.)

Being stuck with a 2.6.21 version kernel isn't the hottest thing around... I really would like to use zram swap with the system daemons I run in the linux jail... (I know dalkvik is braindead about swap. However, jailed linux daemons aren't so dumb.)

As for the issue wit switching to host mode;

He can be clever, and mount /sdcard with a tmpfs mount, then use mount -bind on top later.

[foil]

Install the system wide Adblock Plus.  You get it direct from their website after google blocked it, blocks in app ads and everything else as a system driver(rooted) rather than a browser plugin.

You can also get adblock plus plugin in Firefox for Android as you sometimes need to turn off system wide blocking if the odd app breaks with it.

Also for saving apps, if you are downloading them from other places rather than the Play store (yarr) you will usually have to download them to the pc then copy them to the tablet, just dont delete them from the pc to keep them as a backup.