Choosing an Android Tablet for the DRO Application

When I started the Android Digital Readout project my only tablet was a rooted B&N Nook Color. At that time it was one of the few tablets that could be had for under $300, but it came with a few limitations. First of all, it required rooting to be usable, which voided the warranty etc. Second, the Bluetooth was included “by accident”. While Bluetooth was a part of the wireless chip, the feature was not fully implemented on the hardware level, and was lacking an antenna. This reduced the range to a few feet at most. Finally, even the custom ROMs only went up to Android v2.3 [Gingerbread]. There is nothing inherently wrong with this particular version, but Honeycomb (3.0) and Ice Cream Sandwich (4.0) have much better tablet support.

Please note that there is a Cyanogenmod 9 ROM for Nook. In my experience, while Cyanogenmod 7 has been pretty stable as of late (that's what's installed on the Nook now), CM9 is still largely work in progress. Although it's theoretically possible to get Ice Cream Sandwich on the Nook, it wouldn't be a viable option.

I hesitated to move up to Honeycomb, since Gingerbread still has almost double the market share of ICE (little over 50% vs. approx. 25% for ICE). After a few weeks of “soul searching” I've decided to go for it. The new APIs are much nicer than what is available in 2.x. Since I have precious little time to work on the project, my time will be better spent on the DRO features rather than reinventing the wheels that will become obsolete in a year or two. Even though this means that the DRO won't run on an old cell phone/Nook/Kindle Fire, in the long run the tradeoffs are worth it (at least in my opinion).

With that in mind, here are the hardware requirements for the DRO as it stands right now:

Must Have Features

• Android 3.0 Honeycomb 4.0 Ice Cream Sandwich or newer. The app will run on 3.0, but given the choice, 4.0 is a better option.
  UPDATE Jul 8, 2013: The upcoming version will no longer support since the limited (1.6%) usage of 3.0 does not justify the required compromises
• Bluetooth. At this point Bluetooth is the only communication method implemented. In the future I am planning to add USB support as well.
• Touch screen. The UI can theoretically work without a touch screen, but that defeats the whole point of this project.

Nice to Have Features

• Screen size of 7” or larger. The application will run fine on Android Phones, but the buttons will be very tiny. The larger the screen, the better obviously, but 7” feels reasonably well, even with my “fat fingers”
• 1024x600 display resolution (WSVGA) or better. Same as the screen size: the app will run on lower resolution screens, but he user experience will be suboptimal.
• WiFi. This is mostly for future expansions, but I'm planning to add some features that work better with an internet connection.
• SD or MicroSD card slot. Again, this is mostly for future expansions.

As you might've noticed, I didn't mention anything about the CPU, RAM, Storage etc. As far as the DRO application is concerned, even single-processor tablets with modest RAM are practically super computers. After all we are reading some short strings 10-50 times per second and refreshing a styled text screen. A quick search on Amazon found over a dozed good candidates for around $200 or less. The least expensive tablet that satisfied all of the above (at the time of this posting) can be had for as little $120. Spending a bit more will get you a nice name-brand tablet that can be used for much more than a DRO.

Since I intend to use the tablet as the “garage computer”, my top choices were Google Nexus 7 and Samsung Galaxy Tab 3. 2013 version of Nexus 7 retails for $230; Galaxy Tab 3 and the previous version of Nexus 7 can be had for $170 or so. I use galaxy Tab 2 in the garage and Nexus 7 for testing and development and can't complain about either.