Nexus 7

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Code name for the GSM Nexus 7 is Tilapia. The tablet code named Tilapia
  • Android 8 (Oreo)
  • Android 7 (Nougat)
  • Android 6 (Marshmallow) <--- you are here. Dmitry Grinberg build + fixed version of gapps
  • CM12.1 = Android 5.1.1 (Lollipop) Used this for about a year
  • 5.0 : Factory Lollipop has problems
  • 4.4, this one might work Slimkat 4.4
  • 4.2 is where we started


ASUS Nexus 7 2012

  • Tegra 3 quad core Cortex A9 processor, 1.3 GHz
  • Nvidia GeForce ULP (1280x800 WXGA resolution)
  • 1 GB RAM
  • 32 GB flash (16 Gb in non-GSM version)
  • Broadcom BCM4751 GPS chip
  • WLAN 802.11 b/g/[email protected]
  • Bluetooth 3.0 including BLE (4.0) support if you run CM10.2 or newer
  • Camera 1.2 MP
  • Additional sensors: NFC, compass, GPS, gyroscope, accelerometer, proximit, magnetometer, microphone

See teardown at

Welcome to Marshmallow

2017-08-31 Installed MarshMallow, see instructions below. So far so good.

2017-08-30 Tried to escape the Trebuchet crash problem by switching to Nova launcher. This worked for 3 days, now Nova crashes too. Giving up on CM12 (again) and getting Android 6 installed.

There are many pages with instructions, most of them referencing Dmitry Grinberg. For example,

It took a lot of trial and error to find a gapps that worked on my tablet. I tried about 5 different gapps images and got an endless loop of "optimizing 1 of 1 apps". The one I found that works is here.

First install TWRP.

adb reboot recovery
fastboot flash recovery twrp.img
fastboot reboot    hold down power and volume down

Use the arrow keys to select "recovery mode". Install TWRP now (swipe right). Reboot and push images to device.

adb push /sdcard
adb push /sdcard
adb reboot recovery

Use TWRP to do a "wipe" and then to install the two images and then reboot.

RIP CyanogenMod

2017-08-25 Today the copy of Trebuchet on the Tilapia started endlessly crashing (again). I installed ESRI Collector and EOS Pro Tools to use it with an EOS Arrow 100 and it worked fine yesterday. When we tried to use it in the field, kaboom! It was useless. I used the backup system Galaxy Nexus. is gone (the Web site no longer exists), the successor LineageOS is not doing a Tilapia build.

I was able to get another copy of CM12.1 from

See also github:

I have the CWM (ClockWordMod) recovery ROM installed.

I can still get Google Apps from

ADB tools are needed

  1. Install ADB
  2. Plug in the tablet and enable USB debug under developer options

How to back up

There is very little reason for me to make backups of my device, though I have done it religiously in the past. You can make image copies in adb. It works but usually by the time I am ready to install a new ROM I don't care what's on the device. I did this when I installed Ubuntu so that I could re-install the original image when I was done watching everything crash and observing there were only about 3 apps.

What do I have on here? Generally speaking I read books and magazines.

  • Aldiko
  • ESRI Collector
  • Firefox Beta
  • Overdrive
  1. Run adb reboot recovery
  2. Now you have the option of doing a backup.
  3. Be sure you have your Google account information, you will need it later!
  4. After completing the backup, choose wipe data/factory reset

How to use sideload

  1. Run adb reboot recovery Tablet will boot into CWM.
  2. Select the "install zip" on the tablet.
  3. Select the "sideload" options on the tablet.
  4. On the Mac, run adb sideload cm12*.zip and wait for it to upload.
  5. Watch the tablet screen to see the zip unpack and install itself.
  6. Repeat sideload steps for open_gapps*zip file.
  7. Reboot from the tablet.

The tablet should come back up and do its optimization steps and eventually be ready. Or else it will go into an endless loop reloading Trebuchet. :-(

=== How to copy and in install

  1. Copy the gapps .zip-file to /sdcard/ with adb push
  2. Reboot your device to recovery via any one of these methods: 1) using the power-on key combo for your device; 2) running adb reboot recovery from your computer; 3) or via the Advanced Reboot power menu (enabled in Developer Options).
  3. Choose "install zip" or "Apply update" from within recovery, and navigate to the zip-file loaded earlier.
  4. Reboot from recovery back to Android.

CM12 try again

2016-08-10 I try CM12 again. SO FAR IT'S WORKING. SO FAR... still working (2016-10-22)

CM12.1 fail

2015-Dec-23 Merry X-mas and it's time to try CM12.1 (Android 5.1) WHOOO it's BAD this time. Trebuchet and Messaging crash instantly. I managed to get it running by pulling down from the top to get into settings then clearing the data from Trebuchet and Messaging and Clock. I was also able to get USB debugging turned on in there. Remind me to leave it ON so that I can take control via adb.

Now Google Play Service crashes. Dropping back to CM11 once again. Insert Bad Words here. Oh well.

CM11 is back and working again.

Trying CM11 with OpenGapps 4.4 Nano. Small blessing there.

adb push /sdcard/
adb reboot recovery

Then follow onscreen instructions.

CM12 fail


CM12 is still not stable. Pity, I was getting used to it. The Nexus 7 runs about 10-15 minutes then reboots. I am dropping back to CM 10.2.1 (latest "stable") release. I have been pleased with the results of not using Google Apps though.

My current list of installed apps:

Download from F-Droid

  • Fennec FDroid (Firefox variant)
  • K-9 Mail
  • MyOwnNotes (notebook app running on ownCloud)
  • OpenDocument Reader
  • ownCloud (replacement for Dropbox)
  • Squeezer (Logitech Squeezebox client)
  • Twidere (Twitter client)

Download from

  • Bluetooth File Transfer it.medival.blueftp
  • Mapquest
  • Overdrive (works for checked out library books and for personal ebooks)
  • Skype


I left out the NFC clients this time -- I use the phone for that. I left out Sensorium because it runs all the time in background. If I get around to playing with the bluetooth GPS I will reinstall the app for it.


About a month ago I removed CyanogenMod 10 and installed the latest Google image (Lollypop aka 5.1). Lollypop is so-so, nothing strikingly different, but the battery now runs down every day, and things that used to work fine (like the browser) are now painfully slow.

I suspect the battery problem might be due to running a SIP application that keeps the WiFi lit up all the time, I can uninstall that, but it won't fix the speed issue.

So I am loading CyanogenMod back in. I tried CM12 around Dec 2014 and it was awful... I guess I will try again. I did recover the Nexus 7, see "Bricked Nexus 7" below. Yes CM12 WORKS NOW! And it's snappy!

Ditching Google Apps

With CyanogenMod installed, do I really really have to install Google Apps? Please say no! The biggie is that I lose the "Play Store". I don't DO much with the tablet these days anyway other than read web pages.

Plan A - work around Play Store to get the apps I want.

or Plan B - do what this guy suggests -

Cyanogenmod on the Nexus 7

I am trying to install tried CM12 using sideloading. Having successfully transferred the file to the tablet, I am waiting patiently. It says:

detected filesystem ext4 for /dev/block/platform/sdhci-tegra.4/by-name/APP
Patching system image unconditionally
detected filesystem ext4 for /dev/block/platform/sdhci-tegra.4/by-name/APP

I wonder how long this takes... OH. It says "you can tell it's complete if you have regained control over the menu." and I have! Rebooting... it says "Google". Ahhhh it's booting CM12!! Ohhhhh!!! Now it's doing that "optimizing apps" thing. Hope it works better this time! Recovery from the bad version was painful.

Living without Google, Plan A

These are roughly organized in the order that I installed them.

Browse to and download their APK. Enable APK's from Unknown Sources (scary!!!) and install f-droid.apk Open it.

Now use the F-Droid app to install these:

  • Fennec FDroid will replace Firefox. (It's a Firefox version with security tightened up.)
  • BlueGps -- to get GPS from Bluetooth
  • Squeezer -- to control our Logitech Squeezebox
  • NFC Reader -- to read any NFC tags. Just gives tag info, nothing fancy.
  • FareBot reads transport NFC cards. Cool it reads my Clipper!! I will put this on my phone, too.
  • Sensorium - reads sensor data. Note: Runs at startup Great way to see what your tablet sees, and why is that darn GPS turned on again?

Apps in the "Play Store" that are not available in F-Droid can be gotten via if you know the right name. (Copy it from the URL in Google Play Store)

  • Overdrive Media --
  • Bluetooth File Transfer -- so I can copy and post screenshots (Ad suppported)
  • MapQuest - Turn off "Share Additional Information"
  • Skype -

I need lots of MAPS, so I am looking at OpenScienceMap, because it is built on OpenStreetMap and it's using vector tiles. Download the APK directly from their site: Because it's based on OSM, it has the edits I did a couple weeks ago. APPROVED.


  • Barcode Scanner -- (that's the app name) does not work, the camera can't focus close enough.
  • Mifare Classic Tool -- only reads "Mifare Classic" cards - won't read my Clipper card.
  • NFCard -- does not show card info! FAIL!

How can I grab screenshots?

Press power button. There SHOULD be an option there to take a screenshot. If not, go to Settings->Buttons->Power button and you should be able to enable it there.

Once you have a screenshot, it will be saved on the tablet in /Pictures/Screenshots. How do you get it onto your Mac???

  1. Pair the tablet and the Mac.
  2. Install Bluetooth File Transfer and run it. Let it open port 30.
  3. On the Mac, in the Bluetooth icon in the menu bar, select "Browse Files on Device" and select Nexus 7. A dialog will open.
  4. Now you should be able to navigate to the Screenshots folder and pull your file across.
  5. Once you have the file, shut down Bluetooth File Transfer on the tablet by using the "Back" button and selecting "Just Close".

Installing Google Apps later

About an hour after installing CM10, I discovered that there was no Play Store. At that time I was not willing to devote the energy to figure out how to install apps without it, so I relented and installed Google Apps.

Go to the link about to find the Google Apps zip file, and download it to your computer. (I use a Linux virtual machine on a Mac).

On the tablet, I booted into the ClockworkMod by opening a terminal window and typing these commands. You can do the same from the computer using fastboot.

reboot recovery

Then I was able to use this to copy the zip up to the tablet

adb push /sdcard/

Do NOT leave off the last /, else you will remove the symbolic link and replace /sdcard with your zip file. This gives you shell access so you can fix things like this...

adb shell 

Then I used Clockwork to install it.

Bricked Nexus 7

  1. Tried to install CM12. Continuous crashes of Trebuchet, Google Services, Google Play Store, Messaging.
  2. Powered down.
  3. Black screen. Won't start.

I found I could hold down power button for a LONG time and it would boot. I can't get into recovery mode from the device and when I boot into CM12, where once again my apps just crash over and over.

I think I might be able to connect via ADB.

Copying map files for c:geo

  1. Download from
  2. Plug in and detect Nexus, you should see it with "adb devices"
  3. Explore "adb shell" and make a directory to hold the maps. "mkdir /sdcard/osmmaps/"
  4. Copy with adb push /sdcard/osmmaps/

Switching to Ubuntu

Each time I try, Ubuntu is better and there are more reasons to switch. I tried 3 times. There are still no apps.

I am keeping my files here: Projects/UbuntuTouch

Ubuntu Tablet Install

To make Ubuntu Touch development easier I have already switched my desktop to run Ubuntu instead of Mint.

sudo add-apt-repository ppa:phablet-team/tools
sudo apt-get update
sudo apt-get install phablet-tools android-tools-adb android-tools-fastboot
sudo apt-get upgrade

Make a backup

This apparently works to back up my data. Anyway a "full backup" screen came up on the Nexus, and it took a long time.

adb backup -shared
Android 4.2.2
Baseband 1231_0.17.0_1205
Kernel version 3.1.10-g05b777c
Build JDQ39

Download and save a copy of the stock image from Google. NakasiG Nexus 7 Mobile 32 GB

Download Ubuntu image from I found the names of the devices by looking on the site, I have a Tilapia. Maybe I will try a different version of Android soon. There is no Tilapia Ubuntu build so I am using Grouper

-rw-rw-r-- 1 bwilson bwilson 33964483 Nov 17 10:02
-rw-rw-r-- 1 bwilson bwilson  5304320 Nov 17 09:05 saucy-preinstalled-boot-armel+grouper.img
-rw-rw-r-- 1 bwilson bwilson  7288832 Nov 17 10:02 saucy-preinstalled-recovery-armel+grouper.img
-rw-rw-r-- 1 bwilson bwilson 69844256 Nov 17 09:05 saucy-preinstalled-system-armel+grouper.img

See also

  • maguro = Google Galaxy Nexus
  • tilapia = Google Nexus 7 (GSM)