Before I retired, I used to work as an Android engineer in a reputable company. One of the benefits of working in an android team is that we get access to a lot of devices and form factors so we can test our products (the android apps that we build) on various devices. As a result, I have a bunch of android mobile devices and tablets. I will show off the collection in another post some day. After I quit, we were allowed to keep some of the old devices and use them for personal work. However, we are not allowed to sell them or give away to non family members. So I thought I need to put them to good use.


Before I get into the details, I’d like to mention that I have 7 tablets and several phones. I converted one of the phones into a clock for our bedroom. I could not use any tablet because all of them were LCD screens and they don’t become dark enough to be used as a night clock. We like the room to be absolutely dark otherwise our daughter would not sleep. So I converted an old Moto 6 phone with OLED screen into a night clock. The black pixels are completely dark and don’t emit any light unlike the LCD screens which bleed light. This is one place where, even though I wanted to use a tablet, I could not.


Moto 6 as a night clock in our bedroom


Tablet #1

I converted one tablet into a night clock for my parent’s bedroom. My parents have the opposite problem. They want some light in their bedroom. They always slept with a zero watt night light on. They also wanted a clock that is visible in the night. The wall clock is too dark to see even with the night lamp on. So I converted an old Motorola Xoom LCD tablet into a night clock. Since the screen is always emitting light, it also works as a night lamp. Now they don’t have to use a night light. The tablet doubles as a photo frame during the day per my parents request. I also stored some devotional songs in it, so they can listen to the songs every morning. It really is a multipurpose tablet :).


Moto Xoom as a multipurpose device in parents bedroom, masquerading as a night clock, night lamp, photo frame and a music player


Tablet #2

I have another Motorola Xoom tablet that works as a home automation system for our living room. It takes care of controlling the light and temperature (by operating the lights and fan when needed) of the room. I built a home automation system using arduino and various sensors such as light sensor, temperature sensor, motion sensor, relays etc. That system communicates with the android tablet via bluetooth. The information is displayed on the tablet providing a user interface for us to control the home automation manually if needed. Normally it is smart enough to run without any human intervention, but on occasion when we need fan when it does not think the room is hot, we use it.


Moto Xoom tablet used as a home automation frontend


Tablet #3

One Nexus 7 tablet turned into a solar panel monitor and sits in the kitchen. It basically interfaces with my arduino board via bluetooth. The arduino board monitors various parameters such as voltage, current, power etc of solar panel, electricity from grid and our load. The information is sent to the android tablet which it displays in a UI. I built all the solar panel software and hardware if you did not already know. Not just that, this tablet also doubles as a music player for my wife or mom when they are cooking. Again a multipurpose tablet.


Solar panel monitor which doubles up as a music player too


Tablet #4

Another Nexus 7 tablet is with my parents in their home town. That tablet has all our family photos. So when they travel to home town, they use that as a clock and photo frame. They also take the tablet out to show off pictures to relatives and friends when they travel around.


Tablet #5

My daughter uses this tablet for watching videos and doing some drawings on it. Actually she was using an older Nexus 10 tablet (see next section), for watching videos. But later on she started using some drawings and coloring apps on the tablet. I saw that she was struggling to keep the paint inside the lines when using her finger. So I thought it will be nice if she can use a tablet with pen support and I bought a Huawei MediaPad M5 Lite with stylus a couple of years ago. Bad move. She used the stylus for a few days and then completely stopped drawing and painting. Lesson learned. Don’t buy stuff before knowing for sure if the kid really has interest in it. Just kidding :). It was fine. She had fun, but I think giving easy solutions is like spoiling the child. I should have let her struggle with her finger. For the record mrs. reynd was strongly opposed to me buying the tablet with stylus, but I did it anyway.


Daughter's tablet with stylus


Tablet #6 and #7

I use a Nexus 10 tablet as a second monitor for my laptop. This has been a recent development. When I was working, I used to have access to a huge 4K 32” monitor and I can have a bunch of windows all over the place. With my small 15” laptop monitor I was having trouble fitting all my work in one place. Then I thought, why not convert one of my tablets into a second monitor and that is precisely what I did. I still have another Nexus 10 tablet which I can convert into a third screen except there is not enough place on my desk now. May be it is time to upgrade my computer desk :). I will write a separate post on how I converted my android tablet into a second monitor in another post.


An android tablet I use as a second monitor for my laptop


Actually I also used to have an 8th tablet but recently it ceased to function. I tried my best to bring it back to life by using all my soldering skills (which is not much), but it did not work. Perhaps I will write a post about that failed project some day.