[Off-topic] MightyPandora8:
Not sure about where it goes so I am posting it here.

I came across this device from China Mobile IoT that my school distributed to me and my fellow classmates. When it came down to my hand, there is one thing that I have confirmed right away - it's an Android device. So I decided to look up on the Internet but surprisingly NO relevant results were found.

The purpose of me posting here about this device is that I would like to find a way to extend its possibilities - like installing apks or accessing recovery/fastboot or stuff. Or maybe there could be some sort of debug pins and other fancy stuff. Who knows!

Considering the obscurity of this device, I'm going to start with some general information.

Here are some photographs:

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I covered a QR code part because there is IMEI and RFID information - yes, this device has its IMEI printed directly on the front of the device!

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The back after taking off the back cover. My school asked me to add a sticker on the back cover to identify ourselves so it looks opaque on the photo, but it used to look like a "photo frame" that is transparent in the middle so that information on the card may be seen through this cover. The gray shell also has a design that could fit in a card the size of a conventional credit card (at least in China). This inserted card is used with other school devices which require this card for student identification.

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The back of the machine without the card.

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The back with the battery removed. The black part indicates the IMEI.

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The shell removed.

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The PCB extracted from another machine.

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The other side of the PCB.

Known advertised features:

- 4G FDD-LTE/TDD-LTE

- Location service

- Realtime tracking of device (parent can check student's real-time location or set "electronic fences" that warn either sides when student "trespasses" those (this expression is vague but this IS what the manual says))

- Filtered calls (Calls from numbers not included in contacts or a preconfigured whitelist will be rejected immediately without student's

- Call and send a message to a preconfigured SOS contact in emergency (by manually triggering SOS)

- Can have 3 contacts (4 with SOS contact count in)

- An "answering tool" that can show true-or-false or multiple-choice questions by operating on a classroom PC for simple class interactions like questions and polls

* NO WIFI IN THIS DEVICE. WI-FI ABILITIES ARE ONLY USED FOR POSITIONING INDOORS

- Limited SMS support

- Software update (via cellular data.)

Other known information:

- It is Android, as mentioned above. Likely to be Android 4.4.

- Running lsusb on a Linux host after connecting the device to the host shows that it is a Spreadtrum device.

- Its board seems to be named 'GZ02E'. Not sure about whether the GZ is relevant to my location (Guizhou, China).

- The display ribbon cable has only 25 pins.

- No touchscreen.

- No USB OTG. (USB port U=0)

- It is likely that even the most basic Android USB connectivity features were removed/blocked from the device software.

- ADB wasn't "accidentally left enabled."

- I can't access Recovery/Fastboot for now.

Any idea you have to push this thing's boundaries a little bit?