According to IDC's latest worldwide tablet report, the sector declined 7.0% year over year in the second quarter of 2015 (2Q15) with shipments totaling 44.7 million units. Apple remains the number one tablet vendor with 25% market share. However, IDC continues their trend of counting 2-in-1 notebook tablets as tablets which sullies the true statistics of what the pure tablet market really is. Between not breaking out 2-in-1 devices correctly and not accounting for who the "other" 45.6% of the so-called tablet makers are, the statistics seem to be a bungled mess.
It should be noted that the Apple-IBM MobileFirst alliance is a major project bringing custom solutions to specific market segments focused entirely on bringing apps to the enterprise market for tablets, not 2-in-1 devices. No other tablet OEM is making such an effort to advance apps for the tablet.