Strategy Analytics has useful new research that shows that global tablet sales increased by 117 perent in Q1/2013 compared to the Q1/2012. Android is catching up with iOS…
For some reason Strategy Analytics have chosen to exclude white-box tablets in the above figures. If you include white-box tablets, "Android market share of the total tablet market increases significantly to 52% and iOS slips to 41%".
Microsoft experienced "very limited distribution, a shortage of top tier apps, and confusion in the market, are all holding back shipments".
What does this mean for developers? Irrespective of the various OS platform markets shares, it’s clear that at 40.6 million shipments per quarter, tablets are starting to reach similar orders of magnitude as smartphones. (200 million smartphones were shipped in Q1 2013).
Previously, in Q1 2012, it clearly made sense to be developing for smartphones before tablets because tablets were a much smaller market. If the current growth of tablet shipments continues it will be a short time before they will exceed smartphone shipments. This has almost certainly come about due to people not replacing their PCs and instead relying more on tablets.