The Android platform was written by Android Inc. and acquired by Google in 2005 for $50 million in "the best deal [they] ever made." Initially it was for mobile phones. Like many other platforms, it is based on a cut-down version of the common - and free - Linux OS. Android is also distributed free of charge. It doesn't take up much space and it has an application library called the Android Market. Perhaps partly because it's open source, techies tend to prefer it. Smartphone users have been impressed too.
Initially Google produced their own badged mobile phone. However, the company has not been built around providing one-to-one support and delivering a phone direct to customers was not a great success.
For each major version of Android, Google now collaborate with a hardware manufacturer to produce a "Nexus" device which runs on the plain "Vanilla" version of the platform. The latest of these is the Nexus S, built by Samsung. Other manufacturers later add features to the basic platform giving it a "skin" which is sometimes called a UI (User Interface). It is rumoured that a Nexus tablet may appear soon.
The platform has evolved quite fast so that devices can be bought now which run a number of different versions. This introduces some confusion for users and means that some Apps will work differently on different devices. The problem is known as fragmentation. It is exacerbated by Google's attempts to police who gets access to the Android Market (which is the way to access and download apps while using Android). A device has to conform to a number of specifications before it will be allowed official access. In many cases, the Android Market is instead loaded unofficially by the seller or the buyer. This isn't a desirable state of affairs but even with mainstream tablets appearing, the problem persists.
Here's an outline of the different Android versions that you might encounter.
1.5 Cupcake - Android versions have names as well as numbers. They seem to have afternoon coffee connotations. Cupcake is the oldest version that is commonly in use. Some tablets found on EBay may be running it and this is a very good sign that they should be avoided
1.6 Donut (Released 15 September 2009) The Android Market was introduced at this stage, together with support for higher resolution screens and a few other things that one might have expected to be in there from the start. The original Dell Streak was released with this version of Android, and updates took a very long time to arrive. It's quite possible that there are still quite a number of these early tablets around with only the Donut version installed.
2.0/2.1 Eclair (Released October 2009) This release has a number of speed and presentational improvements and support for the Microsoft Exchange business Email server. At this stage Google stipulated that the RAM memory should be at least 512Mb and generally devices with less memory than this are not upgraded. Thus, a device with less than 512Mb should be avoided.
2.2 Froyo (Frozen Yogurt - released 20 May 2010) The upgrades here are quite significant and many devices were left behind at this stage. Here are the highlights:
Flash. This is an application which is used to support many different kinds of video (like BBC iPlayer) and many interactive graphics (like those of Google's own financial webpages). It also supports annoying flickery adverts on web sites and thus it can absorb a tremendous amount of the device's resources displaying things you really don't want to see. The inclusion of Flash, though, is quite significant because it is very widely used and is not available on the iPad. While Samsung succeeded in bringing their Galaxy Tab to the market in October 2010 with a working copy Flash, many others failed (for instance, the Toshiba Folio)
WiFi Hotspotting. Using this, the Froyo phone or tablet can become a WiFi hotspot allowing devices (for instance laptops) which have WiFi but not 3G to access the Internet via the Froyo hotspot. In a similar way, they can gain Internet access through a USB connection to the Froyo device - this is known as USB tethering. The bigger step though is allowing the Froyo device to act as a hotspot. While carriers can and do charge to use the function, it might be that their concerns about it delayed the upgrade. WiFi hotspots could impact on other parts of a carrier's business (like the sale of 3G dongles) and it could increase the amount of data transferred.
2.3 Gingerbread (released 6 December 2010) It adds improved copy and paste, built-in Voice over IP (VoIP) for Skype-like calling, and Near Field Communications (NFC) for making small purchases like sandwiches. Other changes are incremental, but welcome.
2.3.3 is the commonest flavour of gingerbread currently being installed and has just become available for the Samsung Galaxy Tab.
2.3.4 is now available on selected phones, like the Nexus S. It adds video and voice chat to Google Talk.
3 Honeycomb (released February 2011 with the Motorola Xoom) This is the first true tablet version of the platform which makes much better use of a tablet's larger screen, for instance using a task bar running along the bottom edge. Its buttons ( Back, Home and Tasks) are now on the screen, rather than as separate physical buttons on the tablet. [More technically, it also supports resizeable widgets, dual core processors and really needs 1 Gb of RAM.] The general feeling was that Honeycomb and the Xoom were released a little before they were really ready - perhaps as Google and Motorola got caught up in a race to present something just prior to the launch of the iPad 2. So far, the majority of devices released using Honeycomb have had screens of around 10", and the icons might look rather small if the screen is not this big. So, while the earlier Froyo looked pretty out of place on a large screen (see the Advent Vega), perhaps Honeycomb might be impractical on a smaller one.
3.1 came out in May 2011. It fixes a number of the rough edges which drew quite a bit of criticism to the Motorola Xoom around the time of its launch. Updated Xoom tablets now apparently work much better and have featured in TV adverts. This could well be the first tablet platform to sell in big numbers after the introduction of the iPad. It's perhaps an interesting historical curiosity that the first big-selling version of Microsoft Windows was also version 3.1. Released in March 1992, it sold 3 million copies in 2 months.
Ice Cream (rumoured to be released in Summer 2011). This is apparently the release of Android that will bring a Grand Unification between phones and tablets. (Sorry Albert.)
And Lastly
In another step towards replacing the PC, Android added significantly improved support for USB devices as part of both releases 2.3.4 and 3.1. While most devices probably won't work yet if you just plug them into a tablet and wait for something to happen, over the next few months, we can expect to be able to start using flash memory sticks, digital cameras, games controllers, MP3 players and the like, as well as the basic keyboards and mice. One of the most immediate consequences of this change is that you should be interested in whether the tablet you're thinking about buying has a USB host socket.
And here's the current state of play. Crunching these numbers, by the way, suggests that there are around three hundred thousand Honeycomb tablets in use (0.3% of 100 million Android devices) - that's a bit fewer than the sales figures derived from other sources.
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